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.

A328826 Triangle read by rows: binomial(n,k)*(2*n-k)!, n>=0, 0<=k<=n.

Original entry on oeis.org

1, 2, 1, 24, 12, 2, 720, 360, 72, 6, 40320, 20160, 4320, 480, 24, 3628800, 1814400, 403200, 50400, 3600, 120, 479001600, 239500800, 54432000, 7257600, 604800, 30240, 720, 87178291200, 43589145600, 10059033600, 1397088000, 127008000, 7620480, 282240, 5040, 20922789888000
Offset: 0

Views

Author

R. J. Mathar, Oct 28 2019

Keywords

Comments

Vertex-labeled disconnected Goldstone diagrams with n vertices and k single-particle potentials.

Examples

			The triangle starts
    1;
    2     1;
   24    12     2;
  720   360    72     6;
40320 20160  4320   480    24;
		

Crossrefs

Cf. A099022 (row sums), A000142 (diagonal), A010050 (column k=0), A002674 (k=1).

Programs

  • Maple
    A328826 := proc(n,k)
            binomial(n,k)*(2*n-k)! ;
    end proc:
  • Mathematica
    Table[Binomial[n,k](2n-k)!,{n,0,10},{k,0,n}]//Flatten (* Harvey P. Dale, Feb 03 2022 *)

Formula

T(n,k)= binomial(n,k)*(2*n-k)!.
T(n,k) = A328921(n,k) + A328922(n,k). - R. J. Mathar, Nov 02 2019

A328923 Triangle T(n,k) read by rows: connected topologies of Goldstone diagrams with n interactions and k external potentials.

Original entry on oeis.org

1, 2, 1, 6, 4, 1, 76, 60, 18, 2, 2124, 1776, 600, 96, 6, 97968, 84720, 31080, 6000, 600, 24, 6624720, 5876640, 2287440, 497280, 63000, 4320, 120, 615022560, 556466400, 226250640, 53373600, 7832160, 705600, 35280, 720, 74975211360, 68882446080, 28936252800, 7240020480
Offset: 0

Views

Author

R. J. Mathar, Oct 31 2019

Keywords

Examples

			         1;
         2          1;
         6          4          1;
        76         60         18          2;
      2124       1776        600         96          6;
     97968      84720      31080       6000        600         24;
   6624720    5876640    2287440     497280      63000       4320        120;
		

Crossrefs

Formula

T(n,0) = A328921(n,0) / 2^n +(n-1)! .
T(n,k) = 2^(k-n)*A328921(n,k), k>0 .

A328924 Triangle T(n,k) read by rows: connected topologies of the effective potential in Goldstone diagrams with n interactions and k external potentials.

Original entry on oeis.org

1, 0, 1, 2, 0, 1, 12, 12, 6, 2, 300, 336, 168, 48, 6, 13680, 15120, 7560, 2160, 360, 24, 920400, 1000800, 498960, 146880, 27000, 2880, 120, 85004640, 91314720, 45516240, 13698720, 2691360, 342720, 25200, 720, 10314511200, 10981474560, 5476625280, 1675699200, 344433600, 48545280, 4515840, 241920, 5040
Offset: 0

Views

Author

R. J. Mathar, Oct 31 2019

Keywords

Examples

			         1;
         0          1;
         2          0          1;
        12         12          6          2;
       300        336        168         48          6;
     13680      15120       7560       2160        360         24;
    920400    1000800     498960     146880      27000       2880        120;
  85004640   91314720   45516240   13698720    2691360     342720      25200        720;
		

Crossrefs

Formula

T(n,k) = sum_{t=k..n} (-1)^(k+t) *2^(t-k) *binomial(t,k) *A328923(n,t).

A328922 Triangle T(n,k): vertex labeled disconnected Goldstone diagrams with n interactions and k external potentials.

Original entry on oeis.org

0, 0, 0, 4, 4, 1, 128, 120, 36, 4, 6432, 5952, 1920, 288, 18, 494592, 458880, 154560, 26400, 2400, 96, 55027200, 51448320, 17832960, 3279360, 352800, 21600, 600, 8455495680, 7975296000, 2819013120, 543110400, 64350720, 4798080, 211680, 4320, 1729137070080, 1644441845760, 589071974400
Offset: 0

Views

Author

R. J. Mathar, Oct 31 2019

Keywords

Examples

			         0;
         0          0;
         4          4          1;
       128        120         36          4;
      6432       5952       1920        288         18;
    494592     458880     154560      26400       2400         96;
  55027200   51448320   17832960    3279360     352800      21600        600;
8455495680 ...
		

Crossrefs

Formula

T(n,k) + A328921(n,k) = A328826(n,k).
Showing 1-4 of 4 results.