A261976 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give

A261976

Expansion of elliptic_K / elliptic_E in powers of q.

1, 8, 16, -32, -96, 368, 960, -3392, -8896, 31528, 82656, -292704, -767616, 2719024, 7130496, -25257408, -66235776, 234616720, 615265872, -2179359392, -5715218752, 20244124928, 53088812352, -188048196544, -493143336192, 1746784492472, 4580821023328, -16225925666624

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Table of n, a(n) for n=0..27.

FORMULA

G.f.: T3^5 / (T4^4 * T3 + 4*q * d/dq T3) where T3 = theta_3(q) and T4 = theta_4(q).

CROSSREFS

Cf. A004018 (elliptic K(q)), A194094 (elliptic E(q)), A115977 (elliptic k(q)^2).

Cf. A261979 ((K/E)^(1/2)), A261980 ((K/E)^(1/4)).

Cf. A261975 (E/K), A261977 ((E/K)^(1/2)), A261978 ((E/K)^(1/4)).

Sequence in context: A206375 A146541 A363014 * A291124 A239280 A043111

Adjacent sequences: A261973 A261974 A261975 * A261977 A261978 A261979

KEYWORD

sign

AUTHOR

Joerg Arndt, Sep 07 2015

STATUS

approved