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A119430 Expansion of sum{k>=0, 2^k*x^(2k)/prod[j=1..k, 1-j*2x]}. 0
1, 0, 2, 4, 12, 40, 152, 640, 2928, 14400, 75744, 424640, 2527552, 15902848, 105313408, 731376640, 5311088896, 40233525248, 317296341504, 2600091120640, 22099119279104, 194487001540608, 1769555559897088, 16622286300921856 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

FORMULA

a(n)=sum{k=0..n, S2(k,n-k)2^k} where S2(n,k)=A048993(n,k); a(n)=sum{k=0..floor(n/2), S2(n-k,k)2^(n-k)}.

CROSSREFS

Cf. A119429.

Sequence in context: A028329 A204678 A025227 * A074034 A188479 A062962

Adjacent sequences:  A119427 A119428 A119429 * A119431 A119432 A119433

KEYWORD

easy,nonn

AUTHOR

Paul Barry (pbarry(AT)wit.ie), May 19 2006

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Last modified February 15 04:59 EST 2012. Contains 205694 sequences.