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 A104981 Column 1 of triangle A104980; also equals column 0 of triangle A104986, which equals the matrix logarithm of A104980. 7
 0, 1, 2, 7, 33, 191, 1297, 10063, 87669, 847015, 8989301, 103996703, 1303132269, 17589153719, 254509227541, 3931158238735, 64573130459613, 1124144767682215, 20677664894412965, 400760695386194687, 8163539437728923181 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS G. C. Greubel, Table of n, a(n) for n = 0..440 FORMULA From Gary W. Adamson, Jul 14 2011: (Start) Let M = triangle A128175 as an infinite square production matrix (deleting the first "1"):   1, 1, 0, 0, 0, ...   2, 2, 1, 0, 0, ...   4, 4, 3, 1, 0, ...   8, 8, 7, 4, 1, ...   ... a(n) = sum of top row terms of M^(n-1). Example: top row of M^4 = (71, 71, 38, 10, 1), sum = 191 = a(5). (End) a(0) = 1, a(n) = n * a(n-1) + Sum_{j=1..n} A003319(j) * a(n - j), with offset 0 for the term 1. - F. Chapoton, Feb 26 2018 MATHEMATICA T[n_, k_]:= T[n, k]= If[nn): return 0     elif (k==n): return 1     elif (k==n-1): return n     else: return k*T(n, k+1) + sum( T(j, 0)*T(n, j+k+1) for j in (0..n-k-1) ) [T(n, 1) for n in (0..30)] # G. C. Greubel, Jun 07 2021 CROSSREFS Cf. A104980, A104982, A104986, A128175. Sequence in context: A186760 A162661 A299043 * A058797 A121965 A337058 Adjacent sequences:  A104978 A104979 A104980 * A104982 A104983 A104984 KEYWORD nonn AUTHOR Paul D. Hanna, Apr 10 2005 STATUS approved

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Last modified June 22 21:29 EDT 2021. Contains 345393 sequences. (Running on oeis4.)