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A002447 Expansion of 1/(1-2*x^2-3*x^3). 1
1, 0, 2, 3, 4, 12, 17, 36, 70, 123, 248, 456, 865, 1656, 3098, 5907, 11164, 21108, 40049, 75708, 143422, 271563, 513968, 973392, 1842625, 3488688, 6605426, 12505251, 23676916, 44826780, 84869585, 160684308 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

FORMULA

a(n)=2a(n-2)+3a(n-3); a(n)=sum{k=0..floor(n/2), binomial(k, n-2k)2^k*(3/2)^(n-2k)}. - Paul Barry (pbarry(AT)wit.ie), Oct 16 2004

CROSSREFS

Sequence in context: A062946 A060529 A048073 * A007499 A117555 A059810

Adjacent sequences:  A002444 A002445 A002446 * A002448 A002449 A002450

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.