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A154646 A triangular sequence of coefficients: p(x,n)=(-1)^(n + 1)*(x - 1)^(n + 1)*Sum[(3*m + 2)^n*x^m, {m, 0, Infinity}] + (-1)^(n + 1)*(x - 1)^(n + 1)*Sum[(3*m + 1)^n*x^m, {m, 0, Infinity}]. 1
2, 3, 3, 5, 26, 5, 9, 153, 153, 9, 17, 796, 2262, 796, 17, 33, 3951, 25176, 25176, 3951, 33, 65, 19266, 243111, 524876, 243111, 19266, 65, 129, 93477, 2168235, 8760639, 8760639, 2168235, 93477, 129, 257, 453848, 18445820, 127880936, 235517318 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Row sums are:

{2, 6, 36, 324, 3888, 58320, 1049760, 22044960, 529079040, 14285134080,

428554022400,...}.

This results from a modular form bilinear approach summed:

f1(x)=(3*x+1)/(-x); f2(x)=(3*x+2)/(-x).

Contribution from Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Nov 27 2009: I got the previous result from trying to find an infinite sum for higher Sierpinski-Pascal levels: this version was found using the umbral expansion approach.

FORMULA

p(x,n)=(-1)^(-1 + n)* 3^n* (-1 + x)(1 - n) LerchPhi[x, -n, 1/3]+

(-1)^(-1 + n)* 3^n* (-1 + x)(1 - n) LerchPhi[x, -n, 2/3];

p(x,n)=(-1)^(n + 1)*(x - 1)^(n + 1)*Sum[(3*m + 2)^n*x^m, {m, 0, Infinity}] +

(-1)^(n + 1)*(x - 1)^(n + 1)*Sum[(3*m + 1)^n*x^m, {m, 0, Infinity}];

t(n,m)=coefficients(p(x,n))

p(t,x)=Exp[t]*x/((-Exp[3*t] + x)) + Exp[2*t]*x/((-Exp[3*t] + x)) [From Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Nov 27 2009]

EXAMPLE

{2},

{3, 3},

{5, 26, 5},

{9, 153, 153, 9},

{17, 796, 2262, 796, 17},

{33, 3951, 25176, 25176, 3951, 33},

{65, 19266, 243111, 524876, 243111, 19266, 65},

{129, 93477, 2168235, 8760639, 8760639, 2168235, 93477, 129},

{257, 453848, 18445820, 127880936, 235517318, 127880936, 18445820, 453848, 257}, {513, 2210139, 152441730, 1711859886, 5276054772, 5276054772, 1711859886,152441730, 2210139, 513},

{1025, 10802926, 1237317237, 21613648728, 104609410314, 173611661940,104609410314, 21613648728, 1237317237, 10802926, 1025}

MATHEMATICA

Clear[p]; p[x_, n_] = (-1)^(n + 1)*(x - 1)^(n + 1)*Sum[(3*m + 2)^n*x^m, {m, 0, Infinity}]

+ (-1)^(n + 1)*(x - 1)^(n + 1)*Sum[(3*m + 1)^n*x^m, {m, 0, Infinity}];

Table[FullSimplify[ExpandAll[p[x, n]]], {n, 0, 10}];

Table[CoefficientList[FullSimplify[ExpandAll[p[x, n]]], x], {n, 0, 10}];

Flatten[%]

Contribution from Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Nov 27 2009: (Start)

p[t_] = Exp[t]*x/((-Exp[3*t] + x)) + Exp[2*t]*x/((-Exp[3*t] + x));

a = Table[ CoefficientList[FullSimplify[ExpandAll[(n!*(-1 + x)^(n + 1)/x)*SeriesCoefficient[ Series[p[t], {t, 0, 30}], n]]], x], {n, 0, 10}];

Flatten[a] (End)

CROSSREFS

Sequence in context: A064776 A096659 A154695 * A046826 A054892 A104570

Adjacent sequences:  A154643 A154644 A154645 * A154647 A154648 A154649

KEYWORD

nonn,uned,tabl

AUTHOR

Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Jan 13 2009

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Last modified February 15 05:45 EST 2012. Contains 205694 sequences.