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A103973 Expansion of (sqrt(1-8*x^2)+8*x^2+2*x-1)/(2*x*sqrt(1-8*x^2)). 1
1, 2, 4, 4, 24, 16, 160, 80, 1120, 448, 8064, 2688, 59136, 16896, 439296, 109824, 3294720, 732160, 24893440, 4978688, 189190144, 34398208, 1444724736, 240787456, 11076222976, 1704034304, 85201715200, 12171673600, 657270374400 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

G.f.: 1/sqrt(1-8*x^2)+(1-sqrt(1-8*x^2))/(2*x).

a(n) = sum{k=0..floor(n/2), 2^(n-k) * A000108(k) * C(k+1, n-k)}.

CROSSREFS

Cf. A025225, A059304.

Sequence in context: A013140 A155720 A155725 * A129826 A009296 A068554

Adjacent sequences:  A103970 A103971 A103972 * A103974 A103975 A103976

KEYWORD

easy,nonn

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Feb 23 2005

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Last modified February 16 15:58 EST 2012. Contains 205937 sequences.