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 1-5 of 5 results.

A371927 Expansion of 1/(1 - x/(1 - 8*x^2)^(1/4)).

Original entry on oeis.org

1, 1, 1, 3, 5, 17, 33, 113, 237, 803, 1769, 5915, 13493, 44547, 104337, 340527, 814397, 2630857, 6399865, 20486905, 50548997, 160507953, 400834465, 1263577141, 3188428301, 9985916077, 25426685961, 79168607025, 203193847381, 629311885861, 1626634117809
Offset: 0

Views

Author

Seiichi Manyama, Jun 07 2024

Keywords

Crossrefs

Programs

  • Maple
    A371927 := proc(n)
        add(8^k*binomial((n+2*k)/4-1,k),k=0..floor(n/2)) ;
    end proc:
    seq(A371927(n),n=0..70) ; # R. J. Mathar, Jun 07 2024
  • Mathematica
    CoefficientList[Series[1/(1-x/(1-8x^2)^(1/4)),{x,0,30}],x] (* Harvey P. Dale, Dec 20 2024 *)
  • PARI
    a(n) = sum(k=0, n\2, 8^k*binomial((n+2*k)/4-1, k));

Formula

a(n) = Sum_{k=0..floor(n/2)} 8^k * binomial((n+2*k)/4-1,k).

A373512 Expansion of 1/(1 - x/(1 - 16*x^8)^(1/8)).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 5, 7, 9, 11, 13, 15, 17, 37, 61, 89, 121, 157, 197, 241, 289, 545, 877, 1293, 1801, 2409, 3125, 3957, 4913, 8551, 13469, 19891, 28057, 38223, 50661, 65659, 83521, 138227, 213997, 315575, 448297, 618123, 831669, 1096239, 1419857
Offset: 0

Views

Author

Seiichi Manyama, Jun 07 2024

Keywords

Crossrefs

Programs

  • PARI
    a(n) = sum(k=0, n\8, 16^k*binomial(n/8-1, k));

Formula

a(8*n) = 17^(n-1) for n > 0.
a(n) = Sum_{k=0..floor(n/8)} 16^k * binomial(n/8-1,k).

A373627 Expansion of 1 / ( (1 - 8*x^4) * (1 - x/(1 - 8*x^4)^(1/4)) ).

Original entry on oeis.org

1, 1, 1, 1, 9, 11, 13, 15, 81, 109, 141, 177, 729, 1041, 1429, 1901, 6561, 9759, 13981, 19419, 59049, 90483, 133893, 192327, 531441, 832911, 1264173, 1865539, 4782969, 7628799, 11816853, 17828163, 43046721, 69620541, 109646397, 168500385, 387420489, 633634769
Offset: 0

Views

Author

Seiichi Manyama, Jun 11 2024

Keywords

Crossrefs

Programs

  • PARI
    a(n) = sum(k=0, n\4, 8^k*binomial(n/4, k));

Formula

a(4*n) = 9^n for n >= 0.
a(n) = Sum_{k=0..floor(n/4)} 8^k * binomial(n/4,k).
a(n) == 1 (mod 2).

A371490 Expansion of 1/(1 - x/(1 - 8*x)^(1/4)).

Original entry on oeis.org

1, 1, 3, 15, 91, 601, 4155, 29553, 214303, 1575931, 11712599, 87776507, 662224819, 5023611579, 38284084575, 292892970967, 2248271735299, 17307950940833, 133580448494227, 1033263820897777, 8008342899292167, 62179343789159945, 483553052098053915
Offset: 0

Views

Author

Seiichi Manyama, Jun 07 2024

Keywords

Crossrefs

Cf. A373509.

Programs

  • PARI
    a(n) = sum(k=0, n, 8^k*binomial((n+3*k)/4-1, k));

Formula

a(n) = Sum_{k=0..n} 8^k * binomial((n+3*k)/4-1,k).

A373292 Expansion of 1/(1 - x/(1 - 8*x^3)^(1/4)).

Original entry on oeis.org

1, 1, 1, 1, 3, 5, 7, 19, 35, 55, 139, 267, 447, 1077, 2115, 3689, 8595, 17101, 30703, 69797, 140027, 256873, 573167, 1156221, 2156555, 4742759, 9603287, 18149083, 39457727, 80104735, 153007747, 329580959, 670338231, 1291649283, 2761199459, 5623490391
Offset: 0

Views

Author

Seiichi Manyama, Jun 07 2024

Keywords

Crossrefs

Cf. A373509.

Programs

  • PARI
    a(n) = sum(k=0, n\3, 8^k*binomial((n+k)/4-1, k));

Formula

a(n) = Sum_{k=0..floor(n/3)} 8^k * binomial((n+k)/4-1,k).
Showing 1-5 of 5 results.