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A167750 Row sums of triangle A167749. 4
1, 1, 2, 4, 9, 20, 45, 102, 231, 524, 1189, 2699, 6127, 13910, 31581, 71702, 162796, 369622, 839216, 1905419, 4326211, 9822571, 22301948, 50636130, 114968339, 261033373, 592671205, 1345648489, 3055268857, 6936928864, 15750162908 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Hankel transform is A167752.

LINKS

Table of n, a(n) for n=0..30.

FORMULA

G.f.: 1/(1-x/(1-x/(1-x^2/(1-x^3/(1-x^4/(1-...)))))) (continued fraction);

G.f.: 1/(1-x*f(x)), f(x) the g.f. of A005169.

EXAMPLE

G.f. = 1 + x + 2*x^2 + 4*x^3 + 9*x^4 + 20*x^5 + 45*x^6 + 102*x^7 + ...

CROSSREFS

Sequence in context: A080135 A227978 A206741 * A329276 A308435 A188460

Adjacent sequences:  A167747 A167748 A167749 * A167751 A167752 A167753

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Nov 10 2009

STATUS

approved

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Last modified December 16 09:06 EST 2019. Contains 330020 sequences. (Running on oeis4.)