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 1-3 of 3 results.

A079646 A congruence property: a(n) = (A248586(p)-5)/(4*p) where p is the n-th prime.

Original entry on oeis.org

5, 43, 4619, 688390, 23517593780, 4879569381720, 239177513351286095, 55404294334042254028, 3163613989757561167486439, 48119240966975050455116308972625, 12175395259244110756232625177237480, 206515669664553406211418087534393094881690
Offset: 1

Views

Author

Benoit Cloitre, Feb 16 2003

Keywords

Crossrefs

Cf. A248586.

Programs

  • Mathematica
    f[n_] := Sum[Binomial[n, k] * Binomial[2*k, k]^2, {k, 0, n}]; Table[(f[p]-5)/(4*p), {p, Prime[Range[12]]}] (* Amiram Eldar, Apr 20 2025 *)

Extensions

Name corrected by Amiram Eldar, Apr 20 2025

A276536 Binomial sums of the cubes of the central binomial coefficients.

Original entry on oeis.org

1, 9, 233, 8673, 376329, 17800209, 890215361, 46294813497, 2478150328777, 135642353562321, 7556884938829233, 427106589765940137, 24429206859151618209, 1411391470651692285609, 82245902444586364980057, 4828398428680134702936273
Offset: 0

Views

Author

Emanuele Munarini, Nov 16 2016

Keywords

Crossrefs

Cf. Sum_{k = 0..n} binomial(n, k)*binomial(2*k, k)^m: A026375 (m=1), A248586 (m=2), this sequence (m=3).

Programs

  • Magma
    [&+[Binomial(n, k)*Binomial(2*k, k)^3: k in [0..n]]: n in [0..20]]; // Vincenzo Librandi, Nov 30 2016
  • Mathematica
    Table[Sum[Binomial[n, k]Binomial[2k, k]^3, {k, 0, n}], {n, 0, 100}]
  • Maxima
    makelist(sum(binomial(n,k)*binomial(2*k,k)^3,k,0,n),n,0,12);
    

Formula

a(n) = Sum_{k = 0..n} binomial(n, k)*binomial(2*k, k)^3.
Recurrence: (n^3 + 12n^2 + 48n + 64) * a(n+4) - (68n^3 + 714n^2 + 2500n + 2919) * a(n+3) + (198n^3 + 1782n^2 + 5363n + 5397) * a(n+2) - 98 * (2n^3 + 15n^2 + 37n + 30) * a(n+1) + 65 * (n^3 + 6n^2 + 11n + 6) * a(n) = 0.
G.f.: (4/Pi^2) * K(1/2 - 1/2 * sqrt((1-65*t)/(1-t)))^2 / (1-t), where K(x) is complete elliptic integral of the first kind (defined as in MathWorld or in The Wolfram Functions Site).
a(n) ~ 65^(n+3/2) / (512 * Pi^(3/2) * n^(3/2)). - Vaclav Kotesovec, Nov 16 2016
a(n) = 4F3(1/2,1/2,1/2,-n; 1,1,1; -64). - Ilya Gutkovskiy, Nov 25 2016

A278934 a(n) = Sum_{k=0..n} (-1)^(n-k)*binomial(n,k)*binomial(2*k,k)^2.

Original entry on oeis.org

1, 3, 29, 303, 3501, 42663, 538769, 6977547, 92078989, 1232902023, 16700233689, 228356672547, 3147087003201, 43659275921667, 609117615688149, 8539863624592023, 120242239301247309, 1699411957967345127, 24098616839012623769, 342754384909199620803
Offset: 0

Views

Author

Seiichi Manyama, Dec 02 2016

Keywords

Crossrefs

Cf. A248586.
Cf. Sum_{k = 0..n} (-1)^(n-k)*binomial(n, k)*binomial(2*k, k)^m: A002426 (m=1), this sequence (m=2), A276537 (m=3).

Programs

  • Mathematica
    Table[Sum[(-1)^(n-k)*Binomial[n,k]*Binomial[2*k,k]^2, {k, 0, n}], {n, 0, 20}] (* Vaclav Kotesovec, Dec 02 2016 *)
    Table[(-1)^n*HypergeometricPFQ[{1/2, 1/2, -n}, {1, 1}, 16], {n, 0, 20}] (* Vaclav Kotesovec, Dec 02 2016 *)

Formula

Recurrence: n^2*a(n) = (13*n^2 - 13*n + 3)*a(n-1) + 29*(n-1)^2*a(n-2) + 15*(n-2)*(n-1)*a(n-3). - Vaclav Kotesovec, Dec 02 2016
a(n) ~ 15^(n+1) / (16*Pi*n). - Vaclav Kotesovec, Dec 02 2016
Showing 1-3 of 3 results.