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A107104
Absolute row sums of triangle A107102, which is the matrix inverse of A100862.
3
1, 2, 6, 26, 154, 1182, 11254, 128522, 1715802, 26251118, 453132214, 8714516538, 184817376154, 4285657717694, 107880712446966, 2929921866938858, 85399256991014746, 2659096654189212558, 88091786616208073398
OFFSET
0,2
LINKS
W. Mlotkowski, A. Romanowicz, A family of sequences of binomial type, Probability and Mathematical Statistics, Vol. 33, Fasc. 2 (2013), pp. 401-408.
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.
PROG
(PARI) a(n)=if(n==0, 1, 2^n*sum(k=0, n-1, (n+k-1)!/(n-k-1)!/k!/4^k))
(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]))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, May 21 2005
STATUS
approved