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A187008 Row sums of triangle A187005. 6
1, 2, 5, 18, 96, 733, 7501, 97054, 1521112, 28005248, 592218737, 14141289480, 376251253450, 11036022346816, 353747961265089, 12301349824260074, 461216257715290976, 18545829116907146812, 796122011317944176206 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Definition of triangle: A187005(n,k) = [y^k] R_{n-1}(y+y^2) for k=1..n where R_n(y) is the n-th row polynomial for n>1 with R_1(y)=y.

LINKS

Table of n, a(n) for n=1..19.

PROG

(PARI) {a(n)=local(Rn=y); for(m=1, n, Rn=subst(truncate(Rn), y, y+y^2+y*O(y^m))); subst(truncate(Rn), y, 1)}

CROSSREFS

Cf. A187005, A135081, A187006, A187007, A187009.

Sequence in context: A123310 A058119 A075441 * A333837 A075634 A322396

Adjacent sequences:  A187005 A187006 A187007 * A187009 A187010 A187011

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 02 2011

STATUS

approved

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Last modified July 15 23:32 EDT 2020. Contains 335774 sequences. (Running on oeis4.)