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.

A126457 Triangle, read by rows, where T(n,k) = C( C(n+2,3) - C(k+2,3) + 3, n-k) for n>=k>=0.

Original entry on oeis.org

1, 4, 1, 21, 6, 1, 286, 66, 9, 1, 8855, 1540, 171, 13, 1, 501942, 66045, 5984, 378, 18, 1, 45057474, 4582116, 341055, 18424, 741, 24, 1, 5843355957, 470155077, 29034396, 1353275, 47905, 1326, 31, 1, 1029873432159, 66983637864, 3470108187, 140364532
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) + 3, n-k) is illustrated by:
T(n=4,k=1) = C( C(6,3) - C(3,3) + 3, n-k) = C(22,3) = 1540;
T(n=4,k=2) = C( C(6,3) - C(4,3) + 3, n-k) = C(19,2) = 171;
T(n=5,k=2) = C( C(7,3) - C(4,3) + 3, n-k) = C(34,3) = 5984.
Triangle begins:
1;
4, 1;
21, 6, 1;
286, 66, 9, 1;
8855, 1540, 171, 13, 1;
501942, 66045, 5984, 378, 18, 1;
45057474, 4582116, 341055, 18424, 741, 24, 1;
5843355957, 470155077, 29034396, 1353275, 47905, 1326, 31, 1; ...
		

Crossrefs

Columns: A126458, A126459; variants: A126445, A126450, A126454, A107873.

Programs

  • PARI
    T(n,k)=binomial(n*(n+1)*(n+2)/3!-k*(k+1)*(k+2)/3!+3, n-k)

Formula

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

A126456 Column 1 of triangle A126454; a(n) = C( C(n+3,3) + 1, n).

Original entry on oeis.org

1, 5, 55, 1330, 58905, 4187106, 437353560, 63140314380, 12049276177620, 2938311614386005, 891655291709643461, 329600203128234828790, 145830232567505064233200, 76102715775896720790887700
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, Feb 03 2015 *)
  • PARI
    a(n)=binomial((n+1)*(n+2)*(n+3)/3!+1, n)

A126458 Column 0 of triangle A126457; a(n) = C( C(n+2,3) + 3, n).

Original entry on oeis.org

1, 4, 21, 286, 8855, 501942, 45057474, 5843355957, 1029873432159, 236236542585120, 68292983465630781, 24268885951464043344, 10392619362579990298763, 5276256293478688846049120
Offset: 0

Views

Author

Paul D. Hanna, Dec 27 2006

Keywords

Crossrefs

Programs

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