A117271 Column 0 of triangle A117270, which is the matrix log of triangle A117269.
0, 1, 2, 12, 134, 2100, 42302, 1041852, 30331814, 1019056260, 38805685262, 1651676734092, 77703508288694, 4003868870257620, 224255353667365022, 13565588100060643932, 881405810330856632774, 61218510507062012550180
Offset: 0
Keywords
Programs
-
PARI
{a(n)=local(C=matrix(n+1,n+1,r,c,if(r>=c,binomial(r-1,c-1))),M=C,L); for(i=1,n+1,M=(M-M^0)^2+C);L=sum(r=1,#M,-(M^0-M)^r/r);return(L[n+1,1])}
Formula
E.g.f.: A(x) = log( (3-sqrt(5-4*exp(x)))/2 ).
a(n) ~ sqrt(10) * n^(n-1) / (6 * exp(n) * (log(5)-2*log(2))^(n-1/2)). - Vaclav Kotesovec, Feb 25 2014