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 A105618 Row sums of triangle A105615. 1
 1, 3, 15, 107, 991, 11203, 148879, 2270027, 39041151, 747704963, 15784630159, 364256650027, 9124264794271, 246600188525123, 7153677209063439, 221729176945261067, 7313478624348963391, 255786689421734222083 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS PROG (PARI) {a(n)=if(n<0, 0, sum(k=0, n, (matrix(n+1, n+1, m, j, if(m>=j, if(m==j, 1, if(m==j+1, -2*j, polcoeff(1/sum(i=0, m-j, (2*i)!/i!/2^i*x^i)+O(x^m), m-j)))))^-1)[n+1, k+1]))} CROSSREFS Cf. A105615. Sequence in context: A218688 A120016 A074519 * A120732 A245835 A090351 Adjacent sequences:  A105615 A105616 A105617 * A105619 A105620 A105621 KEYWORD nonn AUTHOR Paul D. Hanna, Apr 16 2005 STATUS approved

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Last modified November 30 20:17 EST 2021. Contains 349425 sequences. (Running on oeis4.)