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A158885
G.f. satisfies: A(x) = Sum_{n>=0} x^n * A(2^n*x)^(2n/2^n).
0
1, 1, 3, 17, 191, 4291, 192831, 17339621, 3119465383, 1122599989581, 808041963462203, 1163291544547461767, 3349506451610075179659, 19288870394264558342477991, 222159361747812912367189564823
OFFSET
0,3
EXAMPLE
G.f.: A(x) = 1 + x + 3*x^2 + 17*x^3 + 191*x^4 + 4291*x^5 +...
A(2x)^(1/1) = 1 + 2*x + 12*x^2 + 136*x^3 + 3056*x^4 +...
A(4x)^(2/2) = 1 + 4*x + 48*x^2 + 1088*x^3 + 48896*x^4 +...
A(8x)^(3/4) = 1 + 6*x + 138*x^2 + 6260*x^3 + 571590*x^4 +...
A(16x)^(4/8) = 1 + 8*x + 352*x^2 + 32000*x^3 + 5940736*x^4 +...
A(32x)^(5/16) = 1 + 10*x + 850*x^2 + 154940*x^3 + 58271030*x^4 +...
A(64x)^(6/32) = 1 + 12*x + 1992*x^2 + 727840*x^3 + 552288096*x^4 +...
PROG
(PARI) {a(n)=local(A=1+x); for(n=2, n, A=sum(k=0, n, x^k*subst(A, x, x*2^k+x*O(x^n))^(2*k/2^k))); polcoeff(A, n)}
CROSSREFS
Sequence in context: A163879 A088678 A195067 * A202424 A335343 A133991
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Apr 30 2009
STATUS
approved