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A372138
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G.f. A(x) satisfies A(x) = 1/( 1 - x*A(x)^2*(1 + 4*x*A(x))^(1/2) ).
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0
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1, 1, 5, 24, 149, 945, 6464, 45360, 328661, 2426971, 18244053, 138988092, 1071271988, 8336754044, 65421283160, 517081111568, 4112772482949, 32894217211791, 264391091936095, 2134466592084000, 17300375657257629, 140728012021470193, 1148477345709237844
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = Sum_{k=0..n} 4^(n-k) * binomial(n+2*k,k) * binomial(k/2,n-k)/(n+k+1).
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PROG
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(PARI) a(n) = sum(k=0, n, 4^(n-k)*binomial(n+2*k, k)*binomial(k/2, n-k)/(n+k+1));
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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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