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A107958
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a(n) = term at position 2^n in A107957.
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1
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1, 3, 11, 52, 331, 2949, 38069, 733817, 21670554, 1001901607, 73852354365, 8813580443406, 1725174170633694
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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PROG
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(PARI) {a(n)=local(A=[1, 2]); for(i=1, n, B=vector(#A, k, polcoeff(Ser(A)/(1-x), k-1)+A[2^#binary(#A-1)]); A=concat(A, B); ); sum(k=1, 2^n, A[k])}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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