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.

A156582 Square array T(n, k) = (k+2)^binomial(n, 2) with T(n, 0) = n!, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 1, 1, 3, 6, 1, 1, 4, 27, 24, 1, 1, 5, 64, 729, 120, 1, 1, 6, 125, 4096, 59049, 720, 1, 1, 7, 216, 15625, 1048576, 14348907, 5040, 1, 1, 8, 343, 46656, 9765625, 1073741824, 10460353203, 40320, 1, 1, 9, 512, 117649, 60466176, 30517578125, 4398046511104, 22876792454961, 362880
Offset: 0

Views

Author

Roger L. Bagula, Feb 10 2009

Keywords

Examples

			Square array begins as:
    1,     1,       1,       1,        1,         1 ...;
    1,     1,       1,       1,        1,         1 ...;
    2,     3,       4,       5,        6,         7 ...;
    6,    27,      64,     125,      216,       343 ...;
   24,   729,    4096,   15625,    46656,    117649 ...;
  120, 59049, 1048576, 9765625, 60466176, 282475249 ...;
Antidiagonal triangle begins as:
  1;
  1, 1;
  1, 1, 2;
  1, 1, 3,   6;
  1, 1, 4,  27,    24;
  1, 1, 5,  64,   729,     120;
  1, 1, 6, 125,  4096,   59049,        720;
  1, 1, 7, 216, 15625, 1048576,   14348907,        5040;
  1, 1, 8, 343, 46656, 9765625, 1073741824, 10460353203, 40320;
		

Crossrefs

Programs

  • Magma
    A156582:= func< n,k | k eq 0 select Factorial(n) else (k+2)^Binomial(n,2) >;
    [A156582(k,n-k): k in [0..n], n in [0..12]]; // G. C. Greubel, Jun 28 2021
    
  • Mathematica
    (* First program *)
    T[n_, k_]:= If[k==0, n!, Product[Sum[Binomial[j-1,i]*(k+1)^i, {i,0,j-1}], {j,n}]];
    Table[T[k, n-k], {n,0,12}, {k,0,n}]//Flatten (* modified by G. C. Greubel, Jun 28 2021 *)
    (* Second program *)
    T[n_, k_]:= If[k==0, n!, (k+2)^Binomial[n, 2]];
    Table[T[k, n-k], {n,0,12}, {k,0,n}]//Flatten (* G. C. Greubel, Jun 28 2021 *)
  • Sage
    def A156582(n,k): return factorial(n) if (k==0) else (k+2)^binomial(n,2)
    flatten([[A156582(k,n-k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Jun 28 2021

Formula

T(n,k) = Product_{j=1..n} ( Sum_{i=0..j-1} binomial(j-1, i)*(k+1)^i ) with T(n, 0) = n! (square array).
T(n, k) = (k+2)^binomial(n, 2) with T(n, 0) = n! (square array). - G. C. Greubel, Jun 28 2021

Extensions

Edited by G. C. Greubel, Jun 28 2021