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 1-4 of 4 results.

A176129 Number A(n,k) of solid standard Young tableaux of shape [[n*k,n],[n]]; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 0, 1, 2, 0, 1, 6, 16, 0, 1, 12, 174, 192, 0, 1, 20, 690, 7020, 2816, 0, 1, 30, 1876, 52808, 325590, 46592, 0, 1, 42, 4140, 229680, 4558410, 16290708, 835584, 0, 1, 56, 7986, 738192, 31497284, 420421056, 854630476, 15876096, 0
Offset: 0

Views

Author

Alois P. Heinz, Jul 29 2012

Keywords

Comments

In general, column k is (for k > 1) asymptotic to sqrt((k+2)*(k^2 - 20*k - 8 + sqrt(k*(k+8)^3)) / (8*k^3)) * ((k+2)^(k+2)/k^k)^n / (Pi*n). - Vaclav Kotesovec, Aug 31 2014

Examples

			Square array A(n,k) begins:
  1,      1,        1,         1,          1,           1, ...
  0,      2,        6,        12,         20,          30, ...
  0,     16,      174,       690,       1876,        4140, ...
  0,    192,     7020,     52808,     229680,      738192, ...
  0,   2816,   325590,   4558410,   31497284,   146955276, ...
  0,  46592, 16290708, 420421056, 4600393936, 31113230148, ...
		

Crossrefs

Rows n=0-3 give: A000012, A002378, A215687, A215688.
Main diagonal gives: A215123.

Programs

  • Maple
    b:= proc(x, y, z) option remember; `if`(z>y, b(x, z, y), `if`(z>x, 0,
          `if`({x, y, z}={0}, 1, `if`(x>y and x>z, b(x-1, y, z), 0)+
          `if`(y>0, b(x, y-1, z), 0)+ `if`(z>0, b(x, y, z-1), 0))))
        end:
    A:= (n, k)-> b(n*k, n, n):
    seq(seq(A(n, d-n), n=0..d), d=0..8);
  • Mathematica
    b [x_, y_, z_] := b[x, y, z] = If[z > y, b[x, z, y], If[z > x, 0, If[Union[{x, y, z}] == {0}, 1, If[x > y && x > z, b[x-1, y, z], 0] + If[y > 0, b[x, y-1, z], 0] + If[z > 0, b[x, y, z-1], 0]]]]; a[n_, k_] := b[n*k, n, n]; Table[Table[a[n, d-n], {n, 0, d}], {d, 0, 8}] // Flatten (* Jean-François Alcover, Dec 11 2013, translated from Maple *)

A246619 Number of solid standard Young tableaux of shape [[4*n,n],[n]].

Original entry on oeis.org

1, 20, 1876, 229680, 31497284, 4600393936, 699440711760, 109341854545792, 17445620031680100, 2827280025640259280, 463882742476664594512, 76875122571167921990080, 12845419277094419018993808, 2161338658294952555703260480, 365816910931667192749720139072
Offset: 0

Views

Author

Vaclav Kotesovec, Aug 31 2014

Keywords

Crossrefs

Cf. column k=4 of A176129.

Formula

a(n) ~ sqrt(4*sqrt(3)-6) * 3^(6*n+1) / (Pi * n * 2^(2*n+3)). - Vaclav Kotesovec, Aug 31 2014

A246620 Number of solid standard Young tableaux of shape [[5*n,n],[n]].

Original entry on oeis.org

1, 30, 4140, 738192, 146955276, 31113230148, 6851807953900, 1550766110966400, 358116337203378732, 83984165552626389864, 19937272615715693766528, 4779986445560522545646400, 1155414579663560935856564700, 281212253617692376239817669056
Offset: 0

Views

Author

Vaclav Kotesovec, Aug 31 2014

Keywords

Crossrefs

Cf. Column k=5 of A176129.

Formula

a(n) ~ sqrt(7/10*(13*sqrt(65)-83))/10 * 7^(7*n) / (Pi * n * 5^(5*n)). - Vaclav Kotesovec, Aug 31 2014

A246621 Number of solid standard Young tableaux of shape [[6*n,n],[n]].

Original entry on oeis.org

1, 42, 7986, 1950512, 530931786, 153580152492, 46190668836656, 14274134610246720, 4500027052542851130, 1440557297650459814996, 466776334221187994469180, 152741149363060061495819904, 50388989722150284436348268528, 16737346518387797143628281698720
Offset: 0

Views

Author

Vaclav Kotesovec, Aug 31 2014

Keywords

Crossrefs

Cf. column k=6 of A176129.

Formula

a(n) ~ sqrt((7*sqrt(21)-23)/6)/3 * 8^(8*n) / (Pi * n * 6^(6*n)). - Vaclav Kotesovec, Aug 31 2014
Showing 1-4 of 4 results.