On transformation formulas for theta hypergeometric functions

Using an identity and certain summation formulas for truncated theta hypergeometric series, we establish transformation formulas for finite bilateral theta hypergeometric series. За допомогою однiєї тотожностi та формул пiдсумовування скорочених гiпергеометричних тета-рядiв встановлено формули перет...

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Hauptverfasser: Denis, R.Y., Singh, S.N., Singh, S.P.
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Veröffentlicht: Український математичний журнал 2012
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Zitieren:On transformation formulas for theta hypergeometric functions / R.Y. Denis, S.N. Singh, S.P. Singh // Український математичний журнал. — 2012. — Т. 64, № 7. — С. 994-1000. — Бібліогр.: 3 назв. — англ.

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id nasplib_isofts_kiev_ua-123456789-164454
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spelling Denis, R.Y.
Singh, S.N.
Singh, S.P.
2020-02-09T15:36:41Z
2020-02-09T15:36:41Z
2012
On transformation formulas for theta hypergeometric functions / R.Y. Denis, S.N. Singh, S.P. Singh // Український математичний журнал. — 2012. — Т. 64, № 7. — С. 994-1000. — Бібліогр.: 3 назв. — англ.
1027-3190
https://nasplib.isofts.kiev.ua/handle/123456789/164454
517.5
Using an identity and certain summation formulas for truncated theta hypergeometric series, we establish transformation formulas for finite bilateral theta hypergeometric series.
За допомогою однiєї тотожностi та формул пiдсумовування скорочених гiпергеометричних тета-рядiв встановлено формули перетворення для скiнченних двостороннiх гiпергеометричних тета-рядiв.
en
Український математичний журнал
Український математичний журнал
Короткі повідомлення
On transformation formulas for theta hypergeometric functions
Про формули перетворення для гiпергеометричних тета-функцiй
Article
published earlier
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
title On transformation formulas for theta hypergeometric functions
spellingShingle On transformation formulas for theta hypergeometric functions
Denis, R.Y.
Singh, S.N.
Singh, S.P.
Короткі повідомлення
title_short On transformation formulas for theta hypergeometric functions
title_full On transformation formulas for theta hypergeometric functions
title_fullStr On transformation formulas for theta hypergeometric functions
title_full_unstemmed On transformation formulas for theta hypergeometric functions
title_sort on transformation formulas for theta hypergeometric functions
author Denis, R.Y.
Singh, S.N.
Singh, S.P.
author_facet Denis, R.Y.
Singh, S.N.
Singh, S.P.
topic Короткі повідомлення
topic_facet Короткі повідомлення
publishDate 2012
language English
container_title Український математичний журнал
publisher Український математичний журнал
format Article
title_alt Про формули перетворення для гiпергеометричних тета-функцiй
description Using an identity and certain summation formulas for truncated theta hypergeometric series, we establish transformation formulas for finite bilateral theta hypergeometric series. За допомогою однiєї тотожностi та формул пiдсумовування скорочених гiпергеометричних тета-рядiв встановлено формули перетворення для скiнченних двостороннiх гiпергеометричних тета-рядiв.
issn 1027-3190
url https://nasplib.isofts.kiev.ua/handle/123456789/164454
citation_txt On transformation formulas for theta hypergeometric functions / R.Y. Denis, S.N. Singh, S.P. Singh // Український математичний журнал. — 2012. — Т. 64, № 7. — С. 994-1000. — Бібліогр.: 3 назв. — англ.
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AT singhsn proformuliperetvorennâdlâgipergeometričnihtetafunkcii
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fulltext UDC 517.5 R. Y. Denis (Univ. Gorakhpur, India), S. N. Singh, S. P. Singh (T.D.P.G. College, Jaunpur, India) ON TRANSFORMATION FORMULAE FOR THETA HYPERGEOMETRIC FUNCTIONS ПРО ФОРМУЛИ ПЕРЕТВОРЕННЯ ДЛЯ ГIПЕРГЕОМЕТРИЧНИХ ТЕТА-ФУНКЦIЙ Using an identity and certain summation formulas for truncated theta hypergeometric series, we establish transformation formulas for finite bilateral theta hypergeometric series. За допомогою однiєї тотожностi та формул пiдсумовування скорочених гiпергеометричних тета-рядiв встановлено формули перетворення для скiнченних двостороннiх гiпергеометричних тета-рядiв. 1. Introduction, notations and definitions. Elliptic hypergeometric series and their extensions to theta hypergeometric series has become an increasingly active area of research these days. In the present paper, we have established transformation formulae for bilateral theta hypergeometric series. Special cases of the results established in this paper have also been deduced. A modified Jacobi’s theta function with argument x and nome p is defined by θ(x; p) = [x; p]∞[p/x; p]∞ ≡ [x, p/x; p]∞. (1.1) Also θ(x1, x2, . . . , xr; p) = θ(x1; p)θ(x2; p) . . . θ(xr; p) and [x; p]∞ = ∞∏ r=0 (1− xpr). Following Gasper and Rahman [1] (Chapter 11, (11.2.5) and (11.2.53)) theta shifted factorial is defined by [a; p, q]n = θ(a; p)θ(aq; p) . . . θ(aq n−1; p), n > 0, 1, n = 0. Also [a; q, p]−n = qn(n+1)/2 (−a)n[q/a; q, p]n , n ≥ 1, (1.2) and [a1, a2, . . . , ar; q, p]n = [a1; q, p]n[a2; q, p]n . . . [ar; q, p]n. (1.3) Corresponding to Spiridonov [2], theta hypergeometric series is defined by c© R. Y. DENIS, S. N. SINGH, S. P. SINGH, 2012 994 ISSN 1027-3190. Укр. мат. журн., 2012, т. 64, № 7 ON TRANSFORMATION FORMULAE FOR THETA HYPERGEOMETRIC FUNCTIONS 995 r+1Er [ a1, a2, . . . , ar+1; q, p; z b1, b2, . . . , br ] = ∞∑ n=0 [a1, a2, . . . , ar+1; q, p]nz n [q, b1, b2, . . . , br; q, p]n , (1.4) where max{|z|, |q|, |p|} < 1. Corresponding to Spiridonov [3] a very well-poised theta hypergeometric series is defined by r+1Vr[a1; a6, . . . , ar+1; q, p; z] = = ∞∑ n=0 θ(a1q 2n; p)[a1, a6, . . . , ar+1; q, p; ]n θ(a1; p)[a1q/a6, . . . , a1q/ar+1; q, p]n (zq)n = = r+1Fr [ a1, q √ a1,−q √ a1, q √ a1/p,−q √ a1p, a6, . . . , ar+1; q, p;−z √ a1,− √ a1, √ a1p,− √ a1/p, a1q/a6, . . . , a1q/ar+1 ] . (1.5) A truncated very well-poised theta hypergeometric series is defined by r+1Vr[a1; a6, . . . , ar+1; q, p; z]N = N∑ n=0 θ(a1q 2n; p)[a1, a6, . . . , ar+1; q, p; ]n θ(a1; p)[a1q/a6, . . . , a1q/ar+1; q, p]n (zq)n. (1.6) We call a series of the form n∑ k=−m [a1, a2, . . . , ar+1; q, p]kz k [q, b1, b2, . . . , br; q, p]k a finite bilateral theta hypergeometric series. We shall make use of the following identity: n∑ k=−m λk+m n−k∑ j=0 Aj = n∑ k=−m Ak+m n−k∑ j=0 λj . (1.7) Proof of (1.7). In order to prove (1.7) let us consider the following well know identity: n∑ k=0 λk n−k∑ j=0 Aj = n∑ k=0 Ak n−k∑ j=0 λj (1.8) (cf. Gasper, Rahman [1, p. 321], (11.6.18)). Taking n+m for n and replacing k by k +m in (1.8), we get (1.7) after some simplification. Following summations are also needed in our analysis, 10V9[a; b, c, d, e, q −n; q, p] = [aq, aq/bc, aq/bd, aq/cd; q, p]n [aq/b, aq/c, aq/d, aq/bcd; q, p]n , (1.9) where bcdeq−n = a2q (cf. Gasper, Rahman [1, p. 321], (11.4.1)). Now, setting e = aqn+1 in (1.9), we get 8V7[a; b, c, a/bc; q, p]n = [aq, aq/bc, bq, cq; q, p]n [q, aq/b, aq/c, bcq; q, p]n (1.10) (cf. Gasper, Rahman [1, p. 322], (11.4.10)). Again, we have ISSN 1027-3190. Укр. мат. журн., 2012, т. 64, № 7 996 R. Y. DENIS, S. N. SINGH, S. P. SINGH 10V9[dp; a, b, dpq/c, cdpq n/ab, q−n; q, p2] = [dpq, c/a, c/b, dpq/ab; q, p2]n [c/ab, dpq/a, c, dpq/b; q, p2]n (1.11) (cf. Gasper, Rahman [1, p. 323], (11.4.11)). Now, taking c = abq in (1.11), we get 8V7[dp; a, b, dp/ab; q, p 2]n = [dpq, aq, bq, dpq/ab; q, p2]n [q, abq, dpq/a, dpq/b; q, p2]n . (1.12) We also have n∑ k=0 θ{ad(rst/q)k, (b/d)(r/q)k, (c/d)(s/q)k, (ad/bc)(t/q)k; p} θ(ad, b/d, c/d, ad/bc; p) × × [a; rst/q2, p]k[b; r, p]k[c; s, p]k[ad 2/bc; t, p]kq k [dq; q, p]k[adst/bq; st/q, p]k[adrt/cq; rt/q, p]k[bcrs/dq; rs/q, p]k = = θ(a, b, c, ad2/bc; p)[arst/q2; srt/q2, p]n dθ(ad, b/d, c/d, ad/bc; p)[dq; q, p]n[adst/bq; st/q, p]n × × [br; r, p]n[cs; s, p]n[ad 2t/bc; t, p]n [adrt/cq; rt/q, p]n[bcrs/dq; rs/q, p]n − − θ(d, ad/b, ad/c, bc/d; p) dθ(ad, b/d, /d, ad/bc; p) (1.13) (cf. Gasper, Rahman [1, p. 327], (11.6.9)). Taking d = 1 in the above, we get n∑ k=0 θ{a(rst/q)k, (b)(r/q)k, (c)(s/q)k, (a/bc)(t/q)k; p} θ(a, b, c, a/bc; p) × × [a; rst/q2, p]k[b; r, p]k[c; s, p]k[a/bc; t, p]kq k [q; q, p]k[ast/bq; st/q, p]k[art/cq; rt/q, p]k[bcrs/q; rs/q, p]k = = [arst/q2; srt/q2, p]n[br; r, p]n[cs; s, p]n[at/bc; t, p]n [q; q, p]n[ast/bq; st/q, p]n[art/cq; rt/q, p]n[bcrs/dq; rs/q, p]n . (1.14) 2. Main results. In this section we shall establish our main transformations. We start by setting λk = θ(aq2k; p)[a, b, c, a/bc; q, p]kq k θ(a; p)[q, aq/b, aq/c, bcq; q, p]k and Ak = θ(αp1q 2k 1 ; p21)[αp1, β, γ, αp1/βγ; q1, p 2 1]kq k 1 θ(αp1; p21)[q1, αp1q1/β, αp1q1/γ, βγq1; q1, p 2 1]k in (1.7) and using (1.10) and (1.12), we get θ(aq2m; p)[a, b, c, a/bc; q, p]m[αp1q1, αp1q1/βγ, βq1, γq1; q1, p 2 1]nq m θ(α; p)[q, aq/b, aq/c, bcq; q, p]m[αp1q1/β, αp1q1/γ, βγq1; q1, p21]n × × n∑ k=−m θ(aq2m+2k; p)[aqm, bqm, cqm, aqm/bc; q, p]kq k θ(aq2m; p)[q1+m, aq1+m/b, aq1+m/c, bcq1+m; q, p]k × ISSN 1027-3190. Укр. мат. журн., 2012, т. 64, № 7 ON TRANSFORMATION FORMULAE FOR THETA HYPERGEOMETRIC FUNCTIONS 997 × [q−n1 , βq−n1 /αp1, γq −n 1 /αp1, q −n 1 /βγ; q1, p 2 1]k [q−n1 /αp1, q −n 1 /β, q−n1 /γ, βγq−n1 /αp1; q1; p21]k = = θ(αp1q 2m 1 ; p21)[αp1, β, γ, αp1/βγ; q1, p 2 1]m[aq, bq, cq, aq/bc; q, p]nq m 1 θ(αp1; p21)[q1, αp1q1/β, αp1q1/γ, βγq1; q1, p 2 1]m[q, aq/b, aq/c, bcq; q, p]n × × n∑ k=−m θ(αp1q 2m+2k 1 ; p21)[αp1q m 1 , βq m 1 , γq m 1 , αp1q m 1 /βγ; q1, p 2 1]kq k 1 θ(αp1q2m1 ; p21)[q 1+m 1 , αp1q 1+m 1 /β, αp1q 1+m 1 /γ, βγq1+m 1 ; q1, p21]k × × [q−n, bq−n/a, cq−n/a, q−n/bc; q, p]k [q−n/a, q−n/b, q−n/c, bcq−n/a; q, p]k . (2.1) Next, putting λk = θ(aq2k; p)[a, b, c, a/bc; q, p]kq k θ(a; p)[q, aq/b, aq/c, bcq; q, p]k and Ak = θ{α(rst/q1)k, β(r/q1)k, γ(s/q1)k, (α/βγ)(t/q1)k; p1} θ(α, β, γ, α/βγ; p1) × × [α; rst/q21, p1]k[β; r, p1]k[γ; s, p1]k[α/βγ; t, p1]kq k 1 [q1; q1, p1]k[αst/βq1; st/q1, p1]k[αrt/γq1; rt/q1, p1]k[βγrs/q1; rs/q1, p1]k in (1.7) and using (1.10) and (1.14), we get θ(aq2m; p)[a, b, c, a/bc; q, p]m[αrst/q21; rst/q 2 1, p1]n[βr; r, p1]n θ(a; p)[q, aq/b, aq/c, bcq; q, p]m[q1; q1, p1]n[αst/βq1; st/q1, p1]n × × [γs; s, p1]n[αt/βγ; t, p1]nq m [αrt/γq1; rt/q1, p1]n[βγrs/q1; rs/q1, p1]n × × n∑ k=−m θ(aq2m+2k; p)[aqm, bqm, cqm, aqm/bc; q, p]kq k θ(aq2m; p)[q1+m, aq1+m/b, aq1+m/c, bcq1+m; q, p]k × × [q−n1 ; q1, p1]k[β(st/q1) −n/α; st/q1, p1]k [(rst/q21) −n/α; rst/q21, p1]k[r −n/β; r, p1]k × × [γ(rt/q1) −n/α; rt/q1, p1]k[(rs/q1) −n/βγ; rs/q1, p1]k [s−n/γ; s, p1]k[βγt−n/α; t, p1]k = = [α; rst/q21, p1]m[β; r, p1]m[γ; s, p1]m[α/βγ; t, p1]mq m 1 [αst/βq1; st/q1, p1]n[q1; q1, p1]m[αrt/γq1; rt/q1, p1]m[βγrs/q1; rs/q1, p1]m × × [aq, aq/bc, bq, cq; q, p]n [q, aq/b, aq/c, bcq; q, p]n × × n∑ k=−m θ{α(rst/q1)k+m, β(r/q1) k+m, γ(s/q1) k+m, α(t/q1) k+m/βγ; p1} θ(α, β, γ, α/βγ; p1) × ISSN 1027-3190. Укр. мат. журн., 2012, т. 64, № 7 998 R. Y. DENIS, S. N. SINGH, S. P. SINGH × [α(rst/q21) m; rst/q21, p1]k[βr m; r, p1]k[γs m; s, p1]k [q1+m 1 ; q1, p1]k[α(st/q1)1+m/β; st/q1, p1]k[α(rt/q1)m+1/γ; rt/q1, p1]k × × [αtm/βγ; t, p1]k[q −n, bq−n/a, cq−n/a, q−n/bc; q, p]k [βγ(rs/q1)m+1; rs/q1, p1]k[q−n/a, q−n/b, q−n/c, bcq−n/a; q, p]k . (2.2) Next, if we put λk = θ(apq2k; p2)[ap, b, c, ap/bc; q, p2]kq k θ(ap; p2)[q, apq/b, apq/c, bcq; q, p2]k and Ak = θ{α(rst/q1)k, β(r/q1)k, γ(s/q1)k, α(t/q1)k/βγ; p1} θ(α, β, γ, α/βγ; p1) × × [α; rst/q21, p1]k[β; r, p1]k[γ; s, p1]k[α/βγ; t, p1]kq k 1 [q1; q1, p1]k[αst/βq1; st/q1, p1]k[αrt/γq1; rt/q1, p1]k[βγrs/q1; rs/q1, p1]k in (1.7) and using (1.12) and (1.14), we get θ(apq2m; p2)[ap, b, c, ap/bc; q, p2]mq m θ(ap; p2)[q, apq/b, apq/c, bcq; q, p2]m × × [αrst/q21; rst/q 2 1, p1]n[βr; r, p1]n[γs; s, p1]n[αt/βγ; t, p1]n [q1; q1, p1]n[αst/βq1; st/q1, p1]n[αrt/γq1; rt/q1, p1]n[βγrs/q1; rs/q1, p1]n × × n∑ k=−m θ(apq2m+2k; p2)[apqm, bqm, cqm, apqm/bc; q, p]kq k θ(apq2m; p2)[q1+m, apq1+m/b, apq1+m/c, bcq1+m; q, p]k × × [q−n1 ; q1, p1]k[β(st/q1) −n/α; st/q1, p1]k[γ(rt/q1) −n/α; rt/q1, p1]k [(rst/q21) −n/α; rst/q21, p1]k[r −n/β; r, p1]k[s−n/γ; s, p1]k × × [(rs/q1) −n/βγ; rs/q1, p1]k [βγt−n/α; t, p1]k = = [α; rst/q21, p1]m[β; : r, p1]m[γ; s, p1]m[α/βγ; t, p1]mq m 1 [q1; q1, p1]m[αst/βq1; st/q1, p1]m[αrt/γq1; rt/1, p1]m[βγrs/q1; rs/q1, p1]m × × [aq, aq/bc, bq, cq; q, p]n [q, aq/b, aq/c, bcq; q, p]n × × n∑ k=−m θ{α(rst/q1)k+m, β(r/q1) k+m, γ(s/q1) k+m, α(t/q1) k+m/βγ; p1} θ(α, β, γ, α/βγ; p1) × × [α(rst/q21) m; rst/q21; p1]k[βr m; r, p1]k[γs m; s, p1]k [q1+m 1 , q1, p1]k[α(st/q1)1+m/β; st/q1, p1]k[α(rt/q1)1+m/γ; rt/q1, p1]k × × [αtm/βγ; t, p1]k[q −n, bq−n/ap, cq−n/ap, q−n/bc; q, p2]k [βγ(rs/q1)1+m; rs/q1, p1]k[q−n/ap, q−n/b, q−n/c, bcq−n/ap; q, p]k . (2.3) ISSN 1027-3190. Укр. мат. журн., 2012, т. 64, № 7 ON TRANSFORMATION FORMULAE FOR THETA HYPERGEOMETRIC FUNCTIONS 999 3. Special cases. In this section we shall deduce certain interesting special cases of our results. If we set r = s = t = q1 in (2.2), we get after some simplification θ(aq2m; p)[a, b, c, a/bc; q, p]m[αq1αq1/βγ, βq1, γq1; q1; p1]nq m θ(a; p)[q, aq/b, aq/c, bcq; q, p]m[αq1/β, αq1/γ, βγq1; q1, p1]n × × n∑ k=−m θ(aq2m+2k; p)[aqm, bqm, cqm, aqm/bc; q, p]kq k θ(aq2m; p)[q1+m, aq1+m/b, aq1+m/c, bcq1+m; q, p]k × × [q−n1 , βq−n1 /α, γq−n1 /α, q−n1 /βγ; q1, p1]k [q−n1 /α, q−n1 /β, q−n1 /γ, βγq−n1 /α; q1, p1]k = = [α, β, γ, α/βγ; q1, p1]mq m 1 [aq, bq, cq, aq/bc; q, p]n [q1, αq1/β, αq1/γ, βγq1; q1, p1]m[q, aq/b, aq/c, bcq; q, p]n × × n∑ k=−m θ(αq2m+2k 1 ; p1)[αq m 1 , βq m 1 , γq m 1 , αq m 1 /βγ; q1, p1]kq k 1 θ(α; p1)[q 1+m 1 , αq1+m 1 /β, αq1+m 1 /γ, βγq1+m 1 ; q1, p1]k × × [q−n, bq−n/a, cq−n/a, q−n/bc; q, p]k [q−n/a, q−n/b, q−n/c, bcq−n/a; q, p]k . (3.1) Now, setting α = βγ in (3.1), we get n∑ k=0 θ(aq2k; p)[a, b, c, a/bc; q, p]k θ(a; p)[q, aq/b, aq/c, bcq; q, p]k = [aq, aq/bc, bq, cq; q, p]n [q, aq/b, aq/c, bcq; q, p]n , (3.2) which is (1.9). Again, if we take α = βγq1 in (3.1), we get θ(aq2m; p)θ(βq1, γq1, βγq 1+n 1 , q1+n 1 ; p1)[a, b, c, a/bc; q, p]mq m θ(a; p)θ(q1, βγq1, βq 1+n 1 , γq1+n 1 ; p1)[q, aq/b, aq/c, bcq; q, p]m × × n∑ k=−m θ(aq2m+2k; p)[aqm, bqm, cqm, aqm/bc; q, p]kq k θ(aq2m; p)[q1+m, aq1+m/b, aq1+m/c, bcq1+m; q, p]k × × [q−n1 , q−n−11 /β, q−n−11 /γ, q−n1 /βγ; q1, p1]k [q−n−11 /βγ, q−n1 /β, q−n1 /γ, q−n−1; q1, p1]k = = [β, γ; q1, p1]mq m 1 [aq, bq, cq, aq/bc; q, p]n [γq21, βq 2 1; q1, p1]m[q, aq/b, aq/c, bcq; q, p]n × × n∑ k=−m θ(βγq2m+2k+1 1 ; p1)[βq m 1 , γq m 1 ; q1, p1]kq k 1 θ(βγ; p1)[βq 2+m 1 , γq2+m 1 ; q1, p1]k × × [q−n, bq−n/a, cq−n/a, q−n/bc; q, p]k [q−n/a, q−n/b, q−n/c, bcq−n/a; q, p]k . (3.3) ISSN 1027-3190. Укр. мат. журн., 2012, т. 64, № 7 1000 R. Y. DENIS, S. N. SINGH, S. P. SINGH Next, if we put m = 0 in (3.1), we get [αq1, βq1, γq1, αq1/βγ; q1, p1]n [q1, αq1/β, αq1/γ, βγq1; q1, p1]n × × n∑ k=0 θ(aq2k; p)[a, b, c, a/bc; q, p]k[q −n 1 , βq−n1 /α, γq−n1 /α, q−n1 /βγ; q1, p1]kq k θ(a; p)[q, aq/b, aq/c, bcq; q, p]k[q −n 1 /α, q−n1 /β, q−n1 /γ, βγq−n1 /α; q1, p1]k = = [aq, bq, cq, aq/bc; q, p]n [q, aq/b, aq/c, bcq; q, p]n × × n∑ k=0 θ(aq2k1 ; p1)[α, β, γ, α/βγ; q1, p1]k[q −n, bq−n/a, cq−n/a, q−n/bc; q, p]kq k 1 θ(α; p1)[q1, αq1/β, αq1/γ, βγq1; q1, p1]k[q−n/a, q−n/b, q−n/c, bcq−n/a; q, p]k . (3.4) If we set p = p1 = 0 and q1 = q in (3.4), we get the following interesting transformation: 10φ9 [ a, q √ a− q √ a, b, c, a/bc, βq−n/α, γq−n/α, q−n/βγ, q−n; q; q √ a,− √ a, aq/b, aq/c, bcq, q−n/α, q−n/β, q−n/γ, βγq−n/α ] = = [aq, aq/bc, bq, cq, αq/β, αq/γ, βγq; q]n [aq/b, aq/c, bcq, αq, βq, γq, αq/βγ; q]n × ×10φ9 [ α, q √ α,−q √ α, β, γ, α/βγ, bq−n/a, cq−n/a, q−n/bc, q−n; q; q √ α,− √ α, αq/β, αq/γ, βγq, q−n/a, q−n/b, q−n/c, bcq−n/a ] . (3.5) Now, letting β → 1 in (3.5) we get the following summation of a truncated very well poised 6φ5 6φ5 [ a, q √ a,−q √ a, b, c, a/bc; q; q √ a,− √ a, aq/b, aq/c, bcq ] n = [aq/aq/bc, bq, cq; q]n [q, aq/b, aq/c, bcq; q]n . It is evident that several other interesting results involving theta hypergeometric functions can be established. Acknowledgement. The authors express deep appreciation to the referee for his valuable sug- gestions.This has certainly improved the quality of the paper. They are thankful to the Department of Science and Technology, Govt. of India, New Delhi, for support under major research projects No. SR/S4/MS-461/07 dtd.13.2.2008 entitled “A study of basic hypergeometric functions with spe- cial reference to Ramanujan mathematics”; No. SR/S4/MS:524 dtd.10.2.2008 entitled “Glimpses of Ramanujan’s mathematics in the field of q-series” and No. F.6-2(23)/2008(MRC/NRCB) dtd.5.6.2009, entitled “Investigations of Ramanujan’s work in the field of basic hypergeometric series” sanctioned to them, respectively. The first author is also thankful to the Indian Society of Mathematics and Mathematical Sciences (ISMAMS) for sponsoring his project. 1. Gasper G., Rahman M. Basic hypergeometric series. – Second ed. – Cambridge Univ. Press, 2004. 2. Spiridonov V. P. Theta hypergeometric series // Proc. NATO ASI Asympt. Combin. Appl. Math. Phys. (St.Petersburg, July 9 – 22, 2001). – Dordrecht: Kluwer Acad. Publ., 2002. – P. 307 – 327. 3. Spiridonov V. P. An elliptic incarnation of the Bailey chain // In. Math. Res. Not. – 2002. – 37. – P. 1945 – 1977. Received 14.08.11, after revision — 15.06.12 ISSN 1027-3190. Укр. мат. журн., 2012, т. 64, № 7