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A055252 Triangle of partial row sums (prs) of triangle A055249. 11
1, 4, 1, 13, 5, 1, 38, 18, 6, 1, 104, 56, 24, 7, 1, 272, 160, 80, 31, 8, 1, 688, 432, 240, 111, 39, 9, 1, 1696, 1120, 672, 351, 150, 48, 10, 1, 4096, 2816, 1792, 1023, 501, 198, 58, 11, 1, 9728, 6912, 4608, 2815, 1524, 699, 256, 69, 12, 1, 22784, 16640, 11520 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

In the language of the Shapiro et al. reference (given in A053121) such a lower triangular (ordinary) convolution array, considered as matrix, belongs to the Riordan-group. The G.f. for the row polynomials p(n,x) (increasing powers of x) is (((1-z)^2)/(1-2*z)^3)/(1-x*z/(1-z)).

This is the third member of the family of Riordan-type matrices obtained from A007318(n,m) (Pascal's triangle read as lower triangular matrix) by repeated application of the prs-procedure.

The column sequences appear as A049611(n+1), A001793, A001788, A055580, A055581, A055582, A055583 for m=0..6.

LINKS

Table of n, a(n) for n=0..57.

FORMULA

a(n, m)=sum(A055249(n, k), k=m..n), n >= m >= 0, a(n, m) := 0 if n<m, (sequence of partial row sums in column m).

Column m recursion: a(n, m)= sum(a(j, m), j=m..n-1)+ A055249(n, m), n >= m >= 0, a(n, m) := 0 if n<m.

G.f. for column m: (((1-x)^2)/(1-2*x)^3)*(x/(1-x))^m, m >= 0.

EXAMPLE

{1}; {4,1}; {13,5,1}; {38,18,6,1};...

Fourth row polynomial (n=3): p(3,x)= 38+18*x+6*x^2+x^3

CROSSREFS

Cf. A007318, A055248, A055249. Row sums: A049612(n+1)= A055584(n, 0).

Sequence in context: A002564 A019428 A184753 * A193956 A193843 A116414

Adjacent sequences:  A055249 A055250 A055251 * A055253 A055254 A055255

KEYWORD

easy,nonn,tabl

AUTHOR

Wolfdieter Lang, May 26 2000

STATUS

approved

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Last modified May 19 21:19 EDT 2013. Contains 225436 sequences.