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.

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A138186 A triangular sequence based on expansion of the rational polynomial of A023054 as a Sheffer sequence: p(x,t)=Exp[x*t]*(1 - t^5)/((1 - t)*(1 - t^2)^2*(1 - t^3)).

Original entry on oeis.org

1, 1, 1, 6, 2, 1, 24, 18, 3, 1, 168, 96, 36, 4, 1, 960, 840, 240, 60, 5, 1, 9360, 5760, 2520, 480, 90, 6, 1, 70560, 65520, 20160, 5880, 840, 126, 7, 1, 806400, 564480, 262080, 53760, 11760, 1344, 168, 8, 1, 7983360, 7257600, 2540160, 786240, 120960, 21168
Offset: 1

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Author

Roger L. Bagula and Gary W. Adamson, May 04 2008

Keywords

Comments

Row sums are:
{1, 2, 9, 46, 305, 2106, 18217, 163094, 1700001, 18711730, 232069961};

Examples

			{1},
{1, 1},
{6, 2, 1},
{24, 18, 3, 1},
{168, 96, 36, 4, 1},
{960, 840, 240, 60, 5, 1},
{9360, 5760, 2520, 480, 90, 6, 1},
{70560, 65520, 20160, 5880, 840, 126, 7, 1},
{806400, 564480, 262080, 53760, 11760, 1344, 168, 8, 1},
{7983360, 7257600, 2540160, 786240, 120960, 21168, 2016, 216, 9, 1},
{105235200, 79833600, 36288000, 8467200, 1965600, 241920, 35280, 2880, 270, 10, 1}
		

Crossrefs

Cf. A023054.

Programs

  • Mathematica
    p[t_] = Exp[x*t]*(1 - t^5)/((1 - t)*(1 - t^2)^2*(1 - t^3)) Table[ ExpandAll[n!*SeriesCoefficient[ Series[p[t], {t, 0, 30}], n]], {n, 0, 10}]; a = Table[ CoefficientList[n!*SeriesCoefficient[ Series[p[t], {t, 0, 30}], n], x], {n, 0, 10}]; Flatten[a]

Formula

p(x,t)=Exp[x*t]*(1 - t^5)/((1 - t)*(1 - t^2)^2*(1 - t^3))=Sum(P(x,n)*t^n/n!,{n,0,Infinity}); Out_n,m=n!*Coefficients(P(x,n)).

A008368 Number of orbits on points that are at n steps from the origin in the f.c.c. lattice.

Original entry on oeis.org

1, 1, 3, 4, 7, 8, 13, 14, 20, 22, 29, 31, 40
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. A023054.

Formula

G.f. is conjectured to be (1-x^5)/((1-x)*(1-x^2)^2*(1-x^3)) (a conjecture of Simon Plouffe, see A023054).
Showing 1-2 of 2 results.