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A086662
Stirling transform of Catalan numbers: Sum_{k=0..n} |Stirling1(n,k)|*C(2*k,k)/(k+1).
5
1, 1, 3, 13, 72, 481, 3745, 33209, 329868, 3624270, 43608474, 570008803, 8039735704, 121673027607, 1966231022067, 33786076421499, 615043147866660, 11822938288619344, 239298079351004608, 5086498410027323134, 113278368771499790136, 2637549737582063583274, 64082443707327038140602, 1621782672366231029685407
OFFSET
0,3
LINKS
FORMULA
E.g.f.: hypergeom([1/2], [2], -4*log(1-x)) = 1/(1-x)^2*(BesselI(0, 2*log(1-x))+BesselI(1, 2*log(1-x))).
a(n)=(1/(2*pi))*int(product(x+k,k,0,n-1)*sqrt((4-x)/x),x,0,4) (moment representation). [Paul Barry, Jul 26 2010]
MATHEMATICA
CoefficientList[Series[(BesselI[0, 2*Log[1-x]] + BesselI[1, 2*Log[1-x]]) / (1-x)^2, {x, 0, 20}], x]* Range[0, 20]! (* Vaclav Kotesovec, Mar 02 2014 *)
Table[Sum[Abs[StirlingS1[n, k]]*Binomial[2*k, k]/(k+1), {k, 0, n}], {n, 0, 20}] (* Vaclav Kotesovec, Mar 02 2014 *)
PROG
(PARI) a(n)=sum(k=0, n, abs(stirling(n, k, 1)) * binomial(2*k, k)/(k+1) ); \\ Joerg Arndt, Mar 02 2014
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Sep 12 2003
STATUS
approved