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 1-5 of 5 results.

A126454 Triangle, read by rows, where T(n,k) = C( C(n+2,3) - C(k+2,3) + 2, n-k) for n>=k>=0.

Original entry on oeis.org

1, 3, 1, 15, 5, 1, 220, 55, 8, 1, 7315, 1330, 153, 12, 1, 435897, 58905, 5456, 351, 17, 1, 40475358, 4187106, 316251, 17296, 703, 23, 1, 5373200880, 437353560, 27285336, 1282975, 45760, 1275, 30, 1, 962889794295, 63140314380, 3295144749, 134153712
Offset: 0

Views

Author

Paul D. Hanna, Dec 27 2006

Keywords

Comments

Examples

			Formula: T(n,k) = C( C(n+2,3) - C(k+2,3) + 2, n-k) is illustrated by:
T(n=4,k=1) = C( C(6,3) - C(3,3) + 2, n-k) = C(21,3) = 1330;
T(n=4,k=2) = C( C(6,3) - C(4,3) + 2, n-k) = C(18,2) = 153;
T(n=5,k=2) = C( C(7,3) - C(4,3) + 2, n-k) = C(33,3) = 5456.
Triangle begins:
1;
3, 1;
15, 5, 1;
220, 55, 8, 1;
7315, 1330, 153, 12, 1;
435897, 58905, 5456, 351, 17, 1;
40475358, 4187106, 316251, 17296, 703, 23, 1;
5373200880, 437353560, 27285336, 1282975, 45760, 1275, 30, 1; ...
		

Crossrefs

Columns: A126455, A126456; variants: A126445, A126450, A126457, A107870.

Programs

  • Mathematica
    Table[Binomial[Binomial[n+2,3]-Binomial[k+2,3]+2,n-k],{n,0,10},{k,0,n}]// Flatten (* Harvey P. Dale, Dec 17 2020 *)
  • PARI
    T(n,k)=binomial(n*(n+1)*(n+2)/3!-k*(k+1)*(k+2)/3!+2, n-k)

Formula

T(n,k) = C( n*(n+1)*(n+2)/3! - k*(k+1)*(k+2)/3! + 2, n-k) for n>=k>=0.

A126447 Column 1 of triangle A126445; a(n) = C( C(n+3,3) - 1, n).

Original entry on oeis.org

1, 3, 36, 969, 46376, 3478761, 377447148, 56017460733, 10912535409348, 2703343379981793, 830496702831140346, 310006778438284515093, 138247735223480364826280, 72613463426660610635960445
Offset: 0

Views

Author

Paul D. Hanna, Dec 27 2006

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Binomial[Binomial[n+3,3]-1,n],{n,0,20}] (* Harvey P. Dale, Apr 22 2022 *)
  • PARI
    a(n)=binomial((n+1)*(n+2)*(n+3)/3!-1, n)

A126452 Column 1 of triangle A126450; a(n) = C( C(n+3,3), n).

Original entry on oeis.org

1, 4, 45, 1140, 52360, 3819816, 406481544, 59487568920, 11468588169060, 2818651865383860, 860587163078645431, 319667046321630491484, 141992594868360194121800, 74339194732961502662043600
Offset: 0

Views

Author

Paul D. Hanna, Dec 27 2006

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Binomial[Binomial[n+3,3],n],{n,0,20}] (* Harvey P. Dale, Oct 09 2014 *)
  • PARI
    a(n)=binomial((n+1)*(n+2)*(n+3)/3!, n)

A126455 Column 0 of triangle A126454; a(n) = C( C(n+2,3) + 2, n).

Original entry on oeis.org

1, 3, 15, 220, 7315, 435897, 40475358, 5373200880, 962889794295, 223581013518060, 65230517839369311, 23345156728397937888, 10052806195411162278095, 5126493560257678027274800
Offset: 0

Views

Author

Paul D. Hanna, Dec 27 2006

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Binomial[Binomial[n+2,3]+2,n],{n,0,20}] (* Harvey P. Dale, Dec 08 2018 *)
  • PARI
    a(n)=binomial(n*(n+1)*(n+2)/3!+2, n)

A126459 Column 1 of triangle A126457; a(n) = C( C(n+3,3) + 2, n).

Original entry on oeis.org

1, 6, 66, 1540, 66045, 4582116, 470155077, 66983637864, 12655529067060, 3062465626261470, 923729223066105456, 339813167168828020668, 149762733221010818774320, 77904783726874238769542600
Offset: 0

Views

Author

Paul D. Hanna, Dec 27 2006

Keywords

Crossrefs

Programs

  • PARI
    a(n)=binomial((n+1)*(n+2)*(n+3)/3!+2, n)
Showing 1-5 of 5 results.