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.

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A289639 Coefficients in expansion of -q*E'_10/E_10 where E_10 is the Eisenstein Series (A013974).

Original entry on oeis.org

264, 340560, 141251616, 85062410400, 43377095394864, 23729517350865216, 12591243615814264896, 6769208775901467246912, 3618692733697667332476264, 1939201752717876551124987360, 1038098212042387655796115897440
Offset: 1

Views

Author

Seiichi Manyama, Jul 09 2017

Keywords

Crossrefs

-q*E'_k/E_k: A289635 (k=2), A289636 (k=4), A289637 (k=6), A289638 (k=8), this sequence (k=10), A289640 (k=14).
Cf. A006352 (E_2), A013974 (E_10), A285836, A289024.

Programs

  • Mathematica
    nmax = 20; Rest[CoefficientList[Series[264*x*Sum[k*DivisorSigma[9, k]*x^(k-1), {k, 1, nmax}]/(1 - 264*Sum[DivisorSigma[9, k]*x^k, {k, 1, nmax}]), {x, 0, nmax}], x]] (* Vaclav Kotesovec, Jul 09 2017 *)

Formula

a(n) = Sum_{d|n} d * A289024(d).
a(n) = A288261(n)/3 + A288840(n)/2 + 20*A000203(n).
a(n) = -Sum_{k=1..n-1} A013974(k)*a(n-k) - A013974(n)*n.
G.f.: 1/3 * E_6/E_4 + 1/2 * E_8/E_6 - 5/6 * E_2.
a(n) ~ exp(2*Pi*n). - Vaclav Kotesovec, Jul 09 2017

A289640 Coefficients in expansion of -q*E'_14/E_14 where E_14 is the Eisenstein Series (A058550).

Original entry on oeis.org

24, 393840, 128962656, 87898218720, 42722691563664, 23880530579622336, 12556395110261366976, 6777250576938845733312, 3616836970791932655993144, 1939629997080836352904793760, 1037999388408269242271021494560
Offset: 1

Views

Author

Seiichi Manyama, Jul 09 2017

Keywords

Crossrefs

-q*E'_k/E_k: A289635 (k=2), A289636 (k=4), A289637 (k=6), A289638 (k=8), A289639 (k=10), this sequence (k=14).
Cf. A006352 (E_2), A058550 (E_14), A287964, A289029.

Programs

  • Mathematica
    nmax = 20; Rest[CoefficientList[Series[24*x*Sum[k*DivisorSigma[13, k]*x^(k-1), {k, 1, nmax}]/(1 - 24*Sum[DivisorSigma[13, k]*x^k, {k, 1, nmax}]), {x, 0, nmax}], x]] (* Vaclav Kotesovec, Jul 09 2017 *)

Formula

a(n) = Sum_{d|n} d * A289029(d).
a(n) = 2*A288261(n)/3 + A288840(n)/2 + 28*A000203(n).
a(n) = -Sum_{k=1..n-1} A058550(k)*a(n-k) - A058550(n)*n.
G.f.: 2/3 * E_6/E_4 + 1/2 * E_8/E_6 - 7/6 * E_2.
a(n) ~ exp(2*Pi*n). - Vaclav Kotesovec, Jul 09 2017

A289637 Coefficients in expansion of -q*E'_6/E_6 where E_6 is the Eisenstein Series (A013973).

Original entry on oeis.org

504, 287280, 153540576, 82226602080, 44031499226064, 23578504122108096, 12626092121367162816, 6761166974864088760512, 3620548496603402008959384, 1938773508354916749345180960, 1038197035676506069321210300320
Offset: 1

Views

Author

Seiichi Manyama, Jul 09 2017

Keywords

Crossrefs

-q*E'_k/E_k: A289635 (k=2), A289636 (k=4), this sequence (k=6), A289638 (k=8), A289639 (k=10), A289640 (k=14).
Cf. A000706, A006352 (E_2), A013973 (E_6), A145095, A288851.

Programs

  • Mathematica
    nmax = 20; Rest[CoefficientList[Series[504*x*Sum[k*DivisorSigma[5, k]*x^(k-1), {k, 1, nmax}]/(1 - 504*Sum[DivisorSigma[5, k]*x^k, {k, 1, nmax}]), {x, 0, nmax}], x]] (* Vaclav Kotesovec, Jul 09 2017 *)

Formula

a(n) = Sum_{d|n} d * A288851(d).
a(n) = A288840(n)/2 + 12*A000203(n).
a(n) = -Sum_{k=1..n-1} A013973(k)*a(n-k) - A013973(n)*n.
G.f.: 1/2 * E_8/E_6 - 1/2 * E_2.
a(n) ~ exp(2*Pi*n). - Vaclav Kotesovec, Jul 09 2017

A289141 Table of expansion of j_n in powers of j (A000521).

Original entry on oeis.org

1, -744, 1, 159768, -1488, 1, -36866976, 1069956, -2232, 1, 8507424792, -561444608, 2533680, -2976, 1, -1963211493744, 246683410950, -2028551200, 4550940, -3720, 1, 453039686271072, -96687754014528, 1304194222980, -4850017536, 7121736, -4464, 1
Offset: 0

Views

Author

Seiichi Manyama, Jun 26 2017

Keywords

Examples

			The table a(n,m) starts:
  n\m          0           1        2      3  4
   0:          1
   1:       -744,          1
   2:     159768,      -1488,       1
   3:  -36866976,    1069956,   -2232,     1
   4: 8507424792, -561444608, 2533680, -2976, 1
		

Crossrefs

Cf. A014708 (j_1), A288843 (j_2), A288844 (j_3), A289116 (j_4), A289148 (j_5), A289149 (j_6).
Cf. A288261 (E_6/E_4), A288840 (E_8/E_6).

A289396 a(n) = A288851(n)/12.

Original entry on oeis.org

42, 11949, 4265002, 1713048225, 733858320426, 327479221781677, 150310620492466218, 70428822653977730817, 33523597190772239402026, 16156445902957272648713901, 7865129058155349010009168938, 3860735065245250133098748713633
Offset: 1

Views

Author

Seiichi Manyama, Jul 05 2017

Keywords

Crossrefs

Cf. A013973 (E_6), A109817 (E_6^(1/12)), A288851.

Formula

a(n) = 1 + (1/(24*n)) * Sum_{d|n} A008683(n/d) * A288840(d).

A294183 Coefficients in expansion of E_6/E_8.

Original entry on oeis.org

1, -984, 393768, -129252576, 38684099112, -10970838627984, 3003345011096352, -801909012374388672, 210169391033048138280, -54295810529811041175672, 13867098270790394508774768, -3508693915623201191415922848
Offset: 0

Views

Author

Seiichi Manyama, Feb 11 2018

Keywords

Crossrefs

Cf. A008410 (E_8). A013973 (E_6), A287933, A288840.
E_k/E_{k+2}: A294181 (k=2), A294182 (k=4), this sequence (k=6).

Programs

  • Mathematica
    terms = 12;
    E6[x_] = 1 - 504*Sum[k^5*x^k/(1 - x^k), {k, 1, terms}];
    E8[x_] = 1 + 480*Sum[k^7*x^k/(1 - x^k), {k, 1, terms}];
    E6[x]/E8[x] + O[x]^terms // CoefficientList[#, x]& (* Jean-François Alcover, Feb 23 2018 *)

Formula

Convolution inverse of A288840.
a(n) ~ (-1)^n * 512 * Pi^12 * exp(Pi*sqrt(3)*n) * n / (3 * Gamma(1/3)^18). - Vaclav Kotesovec, Jun 03 2018
Previous Showing 11-16 of 16 results.