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A171203
G.f. satisfies: A(x) = (1 + x*A(2x))^4.
3
1, 4, 38, 708, 24961, 1682688, 220959136, 57266675520, 29497077110720, 30294634141775360, 62134850895148484608, 254691311135373319017472, 2087196424913845641682560512, 34202892422993270952623113994240
OFFSET
0,2
FORMULA
Self-convolution 4th power of A171202 where a(n) = A171202(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))^4); polcoeff(A, n)}
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 05 2009
STATUS
approved