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.

A160738 Toothpick sequence starting from a T formed by 3 toothpicks: a(n)=A160406(n)*3.

Original entry on oeis.org

0, 3, 6, 12, 18, 24, 30, 42, 54, 60, 66, 78, 90, 102, 120, 150, 174, 180, 186, 198, 210, 222, 240, 270, 294, 306, 324, 354, 384, 420, 480, 558, 606, 612, 618, 630, 642, 654, 672, 702, 726, 738, 756, 786, 816, 852, 912, 990, 1038, 1050, 1068, 1098, 1128, 1164
Offset: 0

Views

Author

Omar E. Pol, May 25 2009, Jun 19 2009

Keywords

Crossrefs

Extensions

More terms from R. J. Mathar, Jul 28 2009

A160741 Numerator of P_6(2n), the Legendre polynomial of order 6 at 2n.

Original entry on oeis.org

-5, 10159, 867211, 10373071, 59271739, 227860495, 683245579, 1727242351, 3854919931, 7823790319, 14733641995, 26117017999, 44040338491, 71215667791, 111123125899, 168143944495, 247704167419, 356428995631, 502307776651, 694869638479, 945369767995
Offset: 0

Views

Author

N. J. A. Sloane, Nov 17 2009

Keywords

Crossrefs

Programs

  • Maple
    A160741 := proc(n)
            orthopoly[P](6,2*n) ;
            numer(%) ;
    end proc: # R. J. Mathar, Oct 24 2011
  • Mathematica
    Table[Numerator[LegendreP[6,2n]],{n,0,40}]
  • PARI
    a(n)=numerator(pollegendre(6,n+n)) \\ Charles R Greathouse IV, Oct 24 2011
    
  • PARI
    Vec(-(5 - 10194*x - 795993*x^2 - 4516108*x^3 - 4515933*x^4 - 796098*x^5 - 10159*x^6) / (1 - x)^7 + O(x^30)) \\ Colin Barker, Jul 23 2019

Formula

From Colin Barker, Jul 23 2019: (Start)
G.f.: -(5 - 10194*x - 795993*x^2 - 4516108*x^3 - 4515933*x^4 - 796098*x^5 - 10159*x^6) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>6.
a(n) = -5 + 420*n^2 - 5040*n^4 + 14784*n^6.
(End)

A144126 P_6(2n+1), the Legendre polynomial of order 6 at 2n+1.

Original entry on oeis.org

1, 8989, 213445, 1651609, 7544041, 25289461, 69125869, 163456945, 346843729, 676661581, 1234422421, 2131762249, 3517093945, 5582925349, 8573842621, 12795158881, 18622228129, 26510424445, 37005786469, 50756327161
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. A160739.

Programs

  • Mathematica
    Table[LegendreP[6,2n+1],{n,0,50}] (* N. J. A. Sloane, Nov 17 2009 *)
  • PARI
    a(n)=pollegendre(6,n+n+1) \\ Charles R Greathouse IV, Oct 25 2011
    
  • PARI
    Vec((1 + 8982*x + 150543*x^2 + 346228*x^3 + 150543*x^4 + 8982*x^5 + x^6) / (1 - x)^7 + O(x^30)) \\ Colin Barker, Jul 23 2019

Formula

a(n) = 924*n^6 + 2772*n^5 + 3150*n^4 + 1680*n^3 + 420*n^2 + 42*n+1. - Vaclav Kotesovec, Jul 31 2013
From Colin Barker, Jul 23 2019: (Start)
G.f.: (1 + 8982*x + 150543*x^2 + 346228*x^3 + 150543*x^4 + 8982*x^5 + x^6) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>6.
(End)

Extensions

Definition corrected by N. J. A. Sloane, Nov 17 2009

A160731 First differences of A160730.

Original entry on oeis.org

2, 2, 4, 6, 6, 6, 12, 14, 12, 6, 12, 14, 16, 18, 32, 34, 20, 6, 12, 14, 16, 18, 32, 34, 24, 18, 32, 38, 44, 62, 92, 82, 36, 6, 12, 14, 16, 18, 32, 34, 24, 18, 32, 38, 44, 62, 92, 82, 40, 18, 32, 38, 44, 62
Offset: 1

Views

Author

Omar E. Pol, May 25 2009

Keywords

Examples

			Placing the entries starting from a(4) in a triangle with rows that have length equal to powers of two gives:
6, 6
6, 12, 14, 12
6, 12, 14, 16, 18, 32, 34, 20
6, 12, 14, 16, 18, 32, 34, 24, 18, 32, 38, 44, 62, 92, 82, 36
...
The rows of this triangle tend to 2*A168114.
		

Crossrefs

Formula

From Nathaniel Johnston, Mar 28 2011: (Start)
a(n) = 2*A168113(n)
a(2^(n+2) + 1) = 4(2^n + 1), n >= 1.
(End)

Extensions

Terms after a(11) from Nathaniel Johnston, Mar 28 2011

A160733 First differences of A160732.

Original entry on oeis.org

3, 3, 6, 8, 8, 6, 12, 14, 8, 8, 16, 20, 18, 18, 30, 26, 8, 8, 16, 20, 18, 20, 34, 32, 20, 28, 48, 54, 50, 60, 78, 50, 8, 8, 16, 20, 18, 20, 34, 32, 20, 28, 48, 54, 50, 62, 82, 56, 20, 28, 48, 54, 52, 70, 96
Offset: 1

Views

Author

Omar E. Pol, May 25 2009

Keywords

Crossrefs

Extensions

Terms after a(9) from Nathaniel Johnston, Mar 30 2011
Showing 1-5 of 5 results.