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.

A063396 T(3,n) with T(n,m) as in A063394.

Original entry on oeis.org

1, 15, 47, 131, 343, 863, 2111, 5055, 11903, 27647, 63487, 144383, 325631, 729087, 1622015, 3588095, 7897087, 17301503, 37748735, 82051071, 177733631, 383778815, 826277887, 1774190591, 3800039423, 8120172543, 17314086911, 36842766335, 78248935423
Offset: 0

Views

Author

Floor van Lamoen, Jul 16 2001

Keywords

Crossrefs

Programs

  • Mathematica
    Join[{1},LinearRecurrence[{7,-18,20,-8},{15,47,131,343},30]] (* Harvey P. Dale, Jul 31 2014 *)
  • PARI
    Vec(-(20*x^4-52*x^3+40*x^2-8*x-1)/((x-1)*(2*x-1)^3) + O(x^100)) \\ Colin Barker, May 27 2015

Formula

For n>0, 1/4 * [(n+1)(n+2)2^n + 10(n+1)2^n + 6*2^n - 4]. - Ralf Stephan, May 08 2004
G.f.: -(20*x^4-52*x^3+40*x^2-8*x-1) / ((x-1)*(2*x-1)^3). - Colin Barker, May 27 2015

A063397 T(4,n) with T(n,m) as in A063394.

Original entry on oeis.org

1, 31, 111, 343, 979, 2655, 6943, 17663, 43967, 107519, 259071, 616447, 1451007, 3383295, 7823359, 17956863, 40943615, 92798975, 209190911, 469237759, 1047789567, 2329935871, 5161091071, 11391729663, 25060966399, 54962159615, 120191975423, 262127222783
Offset: 0

Views

Author

Floor van Lamoen, Jul 16 2001

Keywords

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{9,-32,56,-48,16},{1,31,111,343,979,2655},30] (* Harvey P. Dale, Mar 30 2024 *)
  • PARI
    Vec(-(76*x^5-244*x^4+280*x^3-136*x^2+22*x+1) / ((x-1)*(2*x-1)^4) + O(x^100)) \\ Colin Barker, May 27 2015

Formula

a(n) = (6*(-4+27*2^n)+191*2^n*n+15*2^(1+n)*n^2+2^n*n^3)/24 for n>0. - Colin Barker, May 27 2015
G.f.: -(76*x^5-244*x^4+280*x^3-136*x^2+22*x+1) / ((x-1)*(2*x-1)^4). - Colin Barker, May 27 2015

A063398 T(5,n) with T(n,m) as in A063394.

Original entry on oeis.org

1, 63, 255, 863, 2655, 7683, 21287, 57071, 149087, 381311, 958207, 2372095, 5796863, 14007295, 33511423, 79466495, 186949631, 436666367, 1013317631, 2337538047, 5362941951, 12242386943, 27817148415, 62934482943, 141815709695, 318372839423, 712243150847
Offset: 0

Views

Author

Floor van Lamoen, Jul 16 2001

Keywords

Crossrefs

Programs

  • PARI
    Vec(-(260*x^6-996*x^5+1488*x^4-1088*x^3+388*x^2-52*x-1) / ((x-1)*(2*x-1)^5) + O(x^100)) \\ Colin Barker, May 27 2015

Formula

a(n) = (24*(-8+81*2^n)+1671*2^(1+n)*n+803*2^n*n^2+27*2^(1+n)*n^3+2^n*n^4) / 192 for n>0. - Colin Barker, May 27 2015
G.f.: -(260*x^6-996*x^5+1488*x^4-1088*x^3+388*x^2-52*x-1) / ((x-1)*(2*x-1)^5). - Colin Barker, May 27 2015

A063395 T(2n,n) with T(n,m) as in A063394.

Original entry on oeis.org

1, 3, 19, 131, 979, 7683, 62099, 511619, 4271699, 36018179, 305998099, 2615234691, 22459983059, 193665818115, 1675580699539, 14538892408451, 126467748738899, 1102484411211779, 9629327766561299, 84247346901823619, 738200425192338899, 6477139329614712323
Offset: 0

Views

Author

Floor van Lamoen, Jul 16 2001

Keywords

Crossrefs

Equals 4*A084771(n-1) - 1, n>0.

Programs

  • PARI
    m=matrix(50,50):for(i=1,50,m[1,i]=1:m[i,1]=1):for(i=2,50, for(k=1,i,x=i-k+1: if(m[x,k]==0,m[x,k]=sum(n=2,k-1,m[x,n])+sum(n=2,x-1,m[n,k])+k+x-1))):for(n=1,24,print1(m[n,n]",")) /* Ralf Stephan */

Formula

G.f.: 4x/sqrt(1-10x+9x^2) + (1-2x)/(1-x). - Ralf Stephan, Mar 23 2004
Conjecture: (-n+1)*a(n) +(11*n-17)*a(n-1) +(-19*n+43)*a(n-2) +9*(n-3)*a(n-3)=0. - R. J. Mathar, Jun 10 2013

Extensions

More terms from Ralf Stephan, Mar 23 2004
Showing 1-4 of 4 results.