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A107948
Terms at positions 2^n of A107946 for n>=0.
4
1, 1, 2, 5, 16, 68, 399, 3348, 41417, 775234, 22445788, 1024347395, 74876701760, 8888457145166, 1734062627778860
OFFSET
0,3
FORMULA
a(n) = A107946(2^n).
PROG
(PARI) {a(n)=local(A=[1, 1], B=[1]); for(i=1, n-1, B=concat(B, vector(#B, k, polcoeff(Ser(A)/(1-x), #B+k-1))); A=concat(A, B); ); A[2^(n-1)]}
CROSSREFS
Sequence in context: A006116 A122082 A002631 * A220840 A058673 A296675
KEYWORD
nonn
AUTHOR
Paul D. Hanna, May 28 2005
STATUS
approved