A107104 Absolute row sums of triangle A107102, which is the matrix inverse of A100862.
1, 2, 6, 26, 154, 1182, 11254, 128522, 1715802, 26251118, 453132214, 8714516538, 184817376154, 4285657717694, 107880712446966, 2929921866938858, 85399256991014746, 2659096654189212558, 88091786616208073398
Offset: 0
Keywords
Links
- W. Mlotkowski, A. Romanowicz, A family of sequences of binomial type, Probability and Mathematical Statistics, Vol. 33, Fasc. 2 (2013), pp. 401-408.
Programs
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PARI
a(n)=if(n==0,1,2^n*sum(k=0,n-1,(n+k-1)!/(n-k-1)!/k!/4^k))
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PARI
a(n)=local(X=x+x*O(x^n),Y=y+y*O(y^n)); sum(k=0,n,abs((matrix(n+1,n+1,m,j,if(m>=j, (m-1)!*polcoeff(polcoeff(exp(X+Y*X^2/2+X*Y),m-1,x),j-1,y)))^-1)[n+1,k+1]))
Formula
a(n) = 2*A043301(n-1) = 2^n*Sum_{k=0..n-1}(n+k-1)!/(n-k-1)!/k!/4^k for n>0, with a(0) = 1.