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A216585
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G.f.: exp( Sum_{n>=1} A000984(n)*A002426(n)*x^n/n ), where A000984 is the central binomial coefficients and A002426 is the central trinomial coefficients.
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2
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1, 2, 11, 66, 485, 3842, 32712, 291568, 2697610, 25679316, 250190125, 2484270622, 25062816127, 256275246582, 2650947762450, 27697861115740, 291943603838698, 3101066786857876, 33167191013319532, 356924515784037128, 3862299973917286526, 42003704374124712172
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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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Logarithmic derivative yields A216584.
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EXAMPLE
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G.f.: A(x) = 1 + 2*x + 11*x^2 + 66*x^3 + 485*x^4 + 3842*x^5 + 32712*x^6 +...
such that
log(A(x)) = 2*1*x + 6*3*x^2/2 + 20*7*x^3/3 + 70*19*x^4/4 + 252*51*x^5/5 + 924*141*x^6/6 +...+ A000984(n)*A002426(n)*x^n/n +...
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PROG
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(PARI) {a(n)=polcoeff(exp(sum(m=1, n+1, binomial(2*m, m)*polcoeff((1+x+x^2)^m, m)*x^m/m+x*O(x^n))), n)}
for(n=0, 30, print1(a(n), ", "))
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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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