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A371723
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G.f. satisfies A(x) = ( 1 + x * A(x)^(1/4) * (1 + A(x)^(5/4)) )^2.
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2
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1, 4, 18, 100, 623, 4156, 29032, 209656, 1552535, 11724904, 89958000, 699213444, 5494103979, 43570067100, 348274269966, 2803139823512, 22698137859554, 184779492011244, 1511406790180350, 12415340284461312, 102377122022648745, 847144310799588732
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OFFSET
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0,2
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LINKS
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FORMULA
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G.f.: B(x)^4 where B(x) is the g.f. of A370472.
a(n) = 2 * Sum_{k=0..n} binomial(n,k) * binomial(n/2+5*k/2+2,n)/(n/2+5*k/2+2).
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PROG
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(PARI) a(n) = 2*sum(k=0, n, binomial(n, k)*binomial(n/2+5*k/2+2, n)/(n/2+5*k/2+2));
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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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