cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-6 of 6 results.

A261976 Expansion of elliptic_K / elliptic_E in powers of q.

Original entry on oeis.org

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
Offset: 0

Views

Author

Joerg Arndt, Sep 07 2015

Keywords

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)).

Formula

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

A261977 Expansion of (elliptic_E / elliptic_K)^(1/2) in powers of q.

Original entry on oeis.org

1, -4, 16, -48, 112, -248, 576, -1248, 2272, -3988, 8672, -18192, 23616, -23000, 100992, -304032, 41152, 970552, 1972816, -11299824, -9904096, 80729472, 95978688, -676487328, -755649408, 5483063076, 6371808608, -45452602080, -53224627584, 378628636264, 449486486400, -3179963494272
Offset: 0

Views

Author

Joerg Arndt, Sep 07 2015

Keywords

Crossrefs

Cf. A261975 (E/K), A261978 ((E/K)^(1/4)).
Cf. A261976 (K/E), A261979 ((K/E)^(1/2)), A261980 ((K/E)^(1/4)).
Cf. A004018 (elliptic K(q)), A194094 (elliptic E(q)), A115977 (elliptic k(q)^2).

Formula

See A261975 for the g.f. for E/K.

A261978 Expansion of (elliptic_E / elliptic_K)^(1/4) in powers of q.

Original entry on oeis.org

1, -2, 6, -12, 14, -24, 84, -144, -42, 130, 1656, -3036, -9036, 17784, 76944, -147984, -591274, 1147068, 4784922, -9277164, -38983272, 75690528, 322116804, -625832880, -2687394012, 5224589254, 22613921832, -43985741688, -191670898032, 372970548504, 1634759644944, -3182191744320
Offset: 0

Views

Author

Joerg Arndt, Sep 07 2015

Keywords

Crossrefs

Cf. A261975 (E/K), A261977 ((E/K)^(1/2)).
Cf. A261976 (K/E), A261979 ((K/E)^(1/2)), A261980 ((K/E)^(1/4)).
Cf. A004018 (elliptic K(q)), A194094 (elliptic E(q)), A115977 (elliptic k(q)^2).

Formula

See A261975 for the g.f. for E/K.

A261979 Expansion of (elliptic_K / elliptic_E)^(1/2) in powers of q.

Original entry on oeis.org

1, 4, 0, -16, 16, 120, -128, -928, 1056, 7572, -8960, -63408, 77248, 540504, -672000, -4665824, 5888832, 40656072, -51913728, -356835664, 459890400, 3150052992, -4090609024, -27939033312, 36509767552, 248772971228, -326815190784, -2222432164768, 2932886151552, 19910399315736
Offset: 0

Views

Author

Joerg Arndt, Sep 07 2015

Keywords

Crossrefs

Cf. A261975 (E/K), A261977 ((E/K)^(1/2)), A261978 ((E/K)^(1/4)).
Cf. A261976 (K/E), A261980 ((K/E)^(1/4)).
Cf. A004018 (elliptic K(q)), A194094 (elliptic E(q)), A115977 (elliptic k(q)^2).

Formula

See A261976 for the g.f. for K/E.

A261980 Expansion of (elliptic_K / elliptic_E)^(1/4) in powers of q.

Original entry on oeis.org

1, 2, -2, -4, 14, 24, -92, -176, 694, 1342, -5480, -10612, 44532, 86408, -369328, -717616, 3109078, 6046724, -26473950, -51523620, 227477656, 442950880, -1969014572, -3835720208, 17147433572, 33415180858, -150096433272, -292574352808, 1319581377424, 2572787175656, -11644937717296
Offset: 0

Views

Author

Joerg Arndt, Sep 07 2015

Keywords

Crossrefs

Cf. A261975 (E/K), A261977 ((E/K)^(1/2)), A261978 ((E/K)^(1/4)).
Cf. A261976 (K/E), A261979 ((K/E)^(1/2)).
Cf. A004018 (elliptic K(q)), A194094 (elliptic E(q)), A115977 (elliptic k(q)^2).

Formula

See A261976 for the g.f. for K/E.

A328127 G.f.: E(4*sqrt(x)) / K(4*sqrt(x)), where E(), K() are complete elliptic integrals.

Original entry on oeis.org

1, -8, -16, -128, -1312, -15104, -186112, -2398208, -31898176, -434421248, -6025687552, -84808699904, -1207939190272, -17375932633088, -252046328713216, -3682284573851648, -54130292542567552, -800036763837307904, -11880834659028677632, -177181827571092267008
Offset: 0

Views

Author

Vaclav Kotesovec, Oct 04 2019

Keywords

Crossrefs

Programs

  • Maple
    seq(coeff(series(EllipticE(4*sqrt(x))/EllipticK(4*sqrt(x)), x, 21), x, n), n = 0..20);
  • Mathematica
    CoefficientList[Series[EllipticE[16*x]/EllipticK[16*x], {x, 0, 20}], x]

Formula

a(n) ~ -2^(4*n+1) / (n * log(n)^2) * (1 - (2*gamma + 8*log(2)) / log(n) + (3*gamma^2 + 24*log(2)*gamma + 48*log(2)^2 - Pi^2/2) / log(n)^2 + (-4*gamma^3 + 2*gamma*Pi^2 - 48*gamma^2*log(2) + 8*Pi^2*log(2) - 192*gamma*log(2)^2 - 256*log(2)^3 - 8*Zeta(3)) / log(n)^3 + (5*gamma^4 - 5*gamma^2*Pi^2 + Pi^4/12 + 80*gamma^3*log(2) - 40*gamma*Pi^2*log(2) + 480*gamma^2*log(2)^2 - 80*Pi^2*log(2)^2 + 1280*gamma*log(2)^3 + 1280*log(2)^4 + 40*gamma*Zeta(3) + 160*log(2)*Zeta(3)) / log(n)^4), where gamma is the Euler-Mascheroni constant A001620.
Showing 1-6 of 6 results.