OFFSET
0,3
FORMULA
a(n)=sum(m=1..n, sum(j=0..(n-m)/2, ((n-2*j)!*stirling1(n-m-2*j,m)*sum(k=0..2*j, (-1)^((3*k)/2)*binomial((n-2)/2,(2*j-k)/2)*sum(i=0..k,(2^i*stirling1(n-2*j+i,n-2*j)*binomial(n-2*j+k-1,n-2*j+i-1))/(n-2*j+i)!)))/(n-m-2*j)!)), n>0, a(0)=1.
MATHEMATICA
With[{nn=20}, CoefficientList[Series[(1+ArcSin[x])^ArcSin[x], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Nov 19 2021 *)
PROG
(Maxima)
a(n):=sum(sum(((n-2*j)!*stirling1(n-m-2*j, m)*sum((-1)^((3*k)/2)*binomial((n-2)/2, (2*j-k)/2)*sum((2^i*stirling1(n-2*j+i, n-2*j)*binomial(n-2*j+k-1, n-2*j+i-1))/(n-2*j+i)!, i, 0, k), k, 0, 2*j))/(n-m-2*j)!, j, 0, (n-m)/2), m, 1, n);
CROSSREFS
KEYWORD
sign
AUTHOR
Vladimir Kruchinin, Jun 03 2011
STATUS
approved