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Row sums of triangle A117335.
4

%I #3 Mar 30 2012 18:36:56

%S 1,2,1,4,-9,62,-399,3048,-26045,247298,-2582027,29416876,-363327081,

%T 4837734374,-69105690039,1054490587824,-17122237729589,

%U 294828907099274,-5366869867749347,102988994579465716,-2078107926978317889,43988545301378533742

%N Row sums of triangle A117335.

%F G.f.: A(x) = 1/(1-x)/[Sum_{n>=0} (-1)^n*n!*x^n].

%e A(x) = 1 + 2*x + x^2 + 4*x^3 - 9*x^4 + 62*x^5 - 399*x^6 +-...

%e = 1/(1-x)/(1 - x + 2*x^2 - 6*x^3 + 24*x^4 - 120*x^5 +-...)

%o (PARI) a(n)=polcoeff(1/((1-x)*sum(k=0,n,(-1)^k*k!*x^k)+x*O(x^n)),n)

%Y Cf. A117335 (triangle), A117336 (column 1), A117337 (column 2).

%K sign

%O 0,2

%A _Paul D. Hanna_, Mar 09 2006