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A157526 Triangular sequence from coefficients of the polynomial recursion: p(x,n)=Sum[Binomial[n, m]*p[x, m]*p[x, n - m - 1], {m, 0, n - 1}]. 0
1, 1, 1, 3, 3, 15, 18, 3, 105, 150, 45, 945, 1575, 675, 45, 10395, 19845, 11025, 1575, 135135, 291060, 198450, 44100, 1575, 2027025, 4864860, 3929310, 1190700, 99225, 34459425, 91216125, 85135050, 32744250, 4465125, 99225, 654729075, 1895268375 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Row sums are:

{1, 2, 6, 36, 300, 3240, 42840, 670320, 12111120, 248119200, 5683154400,...}.

The first column is A001147:

{1, 1, 3, 15, 105, 945, 10395, 135135, 2027025, 34459425, 654729075,...}.

FORMULA

p(x,n)=Sum[Binomial[n, m]*p[x, m]*p[x, n - m - 1], {m, 0, n - 1}].

EXAMPLE

{1},

{1, 1},

{3, 3},

{15, 18, 3},

{105, 150, 45},

{945, 1575, 675, 45},

{10395, 19845, 11025, 1575},

{135135, 291060, 198450, 44100, 1575},

{2027025, 4864860, 3929310, 1190700, 99225},

{34459425, 91216125, 85135050, 32744250, 4465125, 99225},

{654729075, 1895268375, 2006754750, 936485550, 180093375, 9823275}

MATHEMATICA

p[x, 0] = 1;

p[x, 1] = x + 1;

p[x_, n_] := Sum[Binomial[n, m]*p[x, m]*p[x, n - m - 1], {m, 0, n - 1}];

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

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

Flatten[%]

CROSSREFS

A001147

Sequence in context: A055634 A133221 A110096 * A153512 A127328 A002891

Adjacent sequences:  A157523 A157524 A157525 * A157527 A157528 A157529

KEYWORD

nonn,tabl,uned

AUTHOR

Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Mar 02 2009

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Last modified February 13 23:23 EST 2012. Contains 205567 sequences.