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A189780
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E.g.f.: 1/(1-arcsin(x)).
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2
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1, 1, 2, 7, 32, 189, 1328, 11019, 104064, 1111641, 13166592, 172006671, 2448559104, 37814647701, 628513744896, 11201565483219, 212867324706816, 4299987047933745
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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)= (n-1)!*sum(m=1..n-1, m*(1+(-1)^(n-m))/2*sum(k=1..n-m (sum(j=1..k, binomial(k,j)*2^(1-j)*sum(i=0..floor(j/2), (-1)^((n-m)/2-i-j)*binomial(j,i)*(j-2*i)^(n-m+j)/(n-m+j)!)))*binomial(k+n-1,n-1)))+n!, n>0, a(0)=1.
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MATHEMATICA
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CoefficientList[Series[1/(1-ArcSin[t]), {t, 0, 100}], t] Table[
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PROG
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(Maxima) a(n):=(n-1)!*sum(m*(1+(-1)^(n-m))/2*sum((sum(binomial(k, j)*2^(1-j)*sum((-1)^((n-m)/2-i-j)*binomial(j, i)*(j-2*i)^(n-m+j)/(n-m+j)!, i, 0, floor(j/2)), j, 1, k))*binomial(k+n-1, n-1), k, 1, n-m), m, 1, n-1)+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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