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.

A186420 a(n) = binomial(2n,n)^4.

Original entry on oeis.org

1, 16, 1296, 160000, 24010000, 4032758016, 728933458176, 138735983333376, 27435582641610000, 5588044012339360000, 1165183173971324375296, 247639903129149250277376, 53472066459540320483696896, 11701285507234585729600000000, 2589980371199606611713600000000
Offset: 0

Views

Author

Emanuele Munarini, Feb 21 2011

Keywords

Examples

			G.f.: 4F3({1/2,1/2,1/2,1/2},{1,1,1},256x) where 4F3 is a hypergeometric series.
		

Crossrefs

Cf. binomial(2n,n)^k: A000984 (k=1), A002894 (k=2), A002897 (k=3), this sequence (k=4).

Programs

  • Mathematica
    Table[Binomial[2n,n]^4,{n,0,20}]
    Table[Coefficient[Series[HypergeometricPFQ[{1/2, 1/2, 1/2, 1/2}, {1, 1, 1}, 256 x], {x, 0, n}], x, n], {n, 0, 14}] (* Michael De Vlieger, Jul 13 2016 *)
  • Maxima
    makelist(binomial(2*n,n)^4,n,0,40);

Formula

a(n) = A000984(n)^4 = A002894(n)^2.
a(n) = binomial(2*n,n)^4 = ( [x^n](1 + x)^(2*n) )^4 = [x^n](F(x)^(16*n)), where F(x) = 1 + x + 25*x^2 + 1798*x^3 + 183442*x^4 + 22623769*x^5 + 3142959012*x^6 + ... appears to have integer coefficients. For similar results see A000897, A002894, A002897, A006480, A008977 and A188662. - Peter Bala, Jul 14 2016
a(n) ~ 256^n/(Pi*n)^2. - Ilya Gutkovskiy, Jul 13 2016

A186414 a(n) = binomial(2n,n)^3/(n+1)^2.

Original entry on oeis.org

1, 2, 24, 500, 13720, 444528, 16099776, 631628712, 26317863000, 1149330319280, 52120705189696, 2437827529099872, 117006104720150464, 5740095404246000000, 286939169121965760000, 14579498741074214418000
Offset: 0

Views

Author

Emanuele Munarini, Feb 21 2011

Keywords

Crossrefs

Programs

  • Magma
    [Binomial(2*n,n)^3/(n+1)^2: n in [0..50]]; // Vincenzo Librandi, Mar 27 2011
  • Mathematica
    Table[Binomial[2n, n]^3/(n + 1)^2, {n, 0, 20}]
  • Maxima
    makelist(binomial(2*n,n)^3/(n+1)^2,n,0,40);
    

Formula

G.f.: 3F2({1/2, 1/2, 1/2}, {2, 2}, 64x), where 3F2 is a hypergeometric function.

A186416 a(n) = binomial(2n,n)^4/(n+1)^3.

Original entry on oeis.org

1, 2, 48, 2500, 192080, 18670176, 2125170432, 270968717448, 37634544090000, 5588044012339360, 875419364366134016, 143310129125665075392, 24338673855047938317568, 4264316875814353400000000, 767401591466550107174400000, 141345980472409642279275210000, 26569505644587874058090478570000
Offset: 0

Views

Author

Emanuele Munarini, Feb 21 2011

Keywords

Crossrefs

Programs

  • Maple
    A186416 := proc(n) binomial(2*n,n)^4/(n+1)^3 ; end proc: # R. J. Mathar, Feb 23 2011
  • Mathematica
    Table[Binomial[2n,n]^4/(n+1)^3,{n,0,40}]
  • Maxima
    makelist(binomial(2*n,n)^4/(n+1)^3,n,0,40);

Formula

G.f.: 4F3(1/2,1/2,1/2,1/2;2,2,2;256*x), where nFm(...;..;.) denotes a generalized hypergeometric series.
a(n) = (A000108(n))^3*A000984(n). - R. J. Mathar, Feb 23 2011

A186418 a(n) = binomial(2*n,n)^4/(n + 1)^2.

Original entry on oeis.org

1, 4, 144, 10000, 960400, 112021056, 14876193024, 2167749739584, 338710896810000, 55880440123393600, 9629613008027474176, 1719721549507980904704, 316402760115623198128384, 59700436261400947600000000
Offset: 0

Views

Author

Emanuele Munarini, Feb 21 2011

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Binomial[2n,n]^4/(n+1)^2,{n,0,40}]
  • Maxima
    makelist(binomial(2*n,n)^4/(n+1)^2,n,0,40);

Formula

G.f.: 4F3({1/2,1/2,1/2,1/2},{1,2,2},256x), where 4F3 is a hypergeometric series.

A186419 a(n) = binomial(2*n,n)^4/(n + 1).

Original entry on oeis.org

1, 8, 432, 40000, 4802000, 672126336, 104133351168, 17341997916672, 3048398071290000, 558804401233936000, 105925743088302215936, 20636658594095770856448, 4113235881503101575668992, 835806107659613266400000000, 172665358079973774114240000000
Offset: 0

Views

Author

Emanuele Munarini, Feb 21 2011

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Binomial[2n,n]^4/(n+1),{n,0,40}]
  • Maxima
    makelist(binomial(2*n,n)^4/(n+1),n,0,12);

Formula

G.f.: 4F3({1/2,1/2,1/2,1/2},{1,1,2},256x), where 4F3 is a hypergeometric series.

A367178 Triangle read by rows. T(n, k) = binomial(n, k)^2 * CatalanNumber(k).

Original entry on oeis.org

1, 1, 1, 1, 4, 2, 1, 9, 18, 5, 1, 16, 72, 80, 14, 1, 25, 200, 500, 350, 42, 1, 36, 450, 2000, 3150, 1512, 132, 1, 49, 882, 6125, 17150, 18522, 6468, 429, 1, 64, 1568, 15680, 68600, 131712, 103488, 27456, 1430, 1, 81, 2592, 35280, 222264, 666792, 931392, 555984, 115830, 4862
Offset: 0

Views

Author

Peter Luschny, Nov 07 2023

Keywords

Examples

			Triangle T(n, k) starts:
  [0] 1;
  [1] 1,  1;
  [2] 1,  4,    2;
  [3] 1,  9,   18,     5;
  [4] 1, 16,   72,    80,     14;
  [5] 1, 25,  200,   500,    350,     42;
  [6] 1, 36,  450,  2000,   3150,   1512,    132;
  [7] 1, 49,  882,  6125,  17150,  18522,   6468,    429;
  [8] 1, 64, 1568, 15680,  68600, 131712, 103488,  27456,   1430;
  [9] 1, 81, 2592, 35280, 222264, 666792, 931392, 555984, 115830, 4862;
		

Crossrefs

Cf. A086618 (row sums), A186415 (central column), A000108 (main diagonal).

Programs

  • Maple
    T := (n, k) -> binomial(n, k)^2 * binomial(2*k, k) / (k + 1):
    seq(seq(T(n, k), k = 0..n), n = 0..9);

Formula

T(n, k) = binomial(n, k)^2 * binomial(2*k, k) / (k + 1).
T(n, k) = [x^n] hypergeom([1/2, -n, -n], [1, 2], 4*x).
Showing 1-6 of 6 results.