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A171209
G.f. satisfies: A(x) = (1 + x*A(2x))^7.
3
1, 7, 119, 3955, 247093, 29355725, 6770018269, 3075928905505, 2774997766597238, 4989660046676105752, 17913062958150482828608, 128508635121001835101510976, 1843071985575998120371392747776
OFFSET
0,2
FORMULA
Self-convolution 7th power of A171208 where a(n) = A171208(n+1)/2^n for n>=0.
PROG
(PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=0, n, A=(1+x*subst(A, x, 2*x))^7); polcoeff(A, n)}
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 05 2009
STATUS
approved