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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.

A177970 Array T(n,m) = A177944(2*n,2*m) read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 26, 1, 1, 99, 99, 1, 1, 244, 622, 244, 1, 1, 485, 2300, 2300, 485, 1, 1, 846, 6423, 12000, 6423, 846, 1, 1, 1351, 15001, 45031, 45031, 15001, 1351, 1, 1, 2024, 30924, 136120, 218774, 136120, 30924, 2024, 1, 1, 2889, 58122, 352698, 831384
Offset: 0

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Author

Roger L. Bagula, May 16 2010

Keywords

Comments

Antidiagonal sums are 1, 2, 28, 200, 1112, 5572, 26540, 122768, 556912, 2490188, ... = 4^d*(d+1/2)-2*d(d+1), d > 0.

Examples

			The table starts in row n=0, column m=0 as:
 1,     1,      1,      1,       1,         1,         1,         1,
 1,    26,     99,    244,     485,       846,      1351,      2024,
 1,    99,    622,   2300,    6423,     15001,     30924,     58122,
 1,   244,   2300,  12000,   45031,    136120,    352698,    813940,
 1,   485,   6423,  45031,  218774,    831384,   2645350,   7354688,
 1,   846,  15001, 136120,  831384,   3879856,  14872836,  49031376,
 1,  1351,  30924, 352698, 2645350,  14872836,  67603876, 260757874,
 1,  2024,  58122, 813940, 7354688,  49031376, 260757874,1163381372,
		

Programs

  • Maple
    T:= (m,n) -> (2*n+1)*binomial(2*m+1+2*n, 2*m)-2*n-2*m:
    seq(seq(T(m,s-m),m=0..s),s=0..10); # Robert Israel, Jul 06 2017
  • Mathematica
    t[n_, m_] = 1/Beta[2*n + 1, 2*m + 1] - 2*n - 2*m;
    a = Table[Table[t[n, m], {m, 0, 10}], {n, 0, 10}];
    Table[Table[a[[m, n - m + 1]], {m, 1, n}], {n, 1, 10}];
    Flatten[%]
  • Python
    from sympy import binomial
    def T(m, n): return (2*n + 1)*binomial(2*m + 1 + 2*n, 2*m) - 2*n - 2*m
    for n in range(11): print([T(m, n - m) for m in range(n + 1)]) # Indranil Ghosh, Jul 06 2017

Formula

T(n,m) = 1/Beta(2*n+1, 2*m+1) - 2*n - 2*m where Beta(a,b) = Gamma(a)*Gamma(b)/Gamma(a+b).

Extensions

Definition rewritten with A177944, examples brought into normal form, closed sum formula - The Assoc. Eds. of the OEIS, Nov 03 2010