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A122877 Expansion of (1-2x-3x^2-(1-x)*sqrt(1-2x-7x^2))/(8x^3). 0
0, 1, 2, 7, 20, 65, 206, 679, 2248, 7569, 25690, 88055, 303964, 1056497, 3693158, 12977655, 45813008, 162400609, 577843890, 2063053991, 7388487460, 26535797729, 95552015614, 344897769991, 1247685613272 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

Binomial transform is A071357.

FORMULA

a(n)=sum{k=0..n, C(n,k)*2^((k-1)/2)C((k-1)/2+1)(1-(-1)^k)/2}, where C(n)=A000108(n); a(n)=(1/pi)*Int(x^n*sqrt(-x^2+2x+7)(x-1)/8,x,1-2sqrt(2),1+2sqrt(2));

CROSSREFS

Sequence in context: A000935 A035071 A055891 * A192680 A000150 A115117

Adjacent sequences:  A122874 A122875 A122876 * A122878 A122879 A122880

KEYWORD

easy,nonn

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Sep 16 2006

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