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 A061261 Limits of diagonals in triangle defined in A061260. 1
 1, 2, 6, 15, 37, 85, 194, 423, 912, 1917, 3974, 8096, 16302, 32382, 63668, 123851, 238756, 456190, 864821, 1627016, 3039845, 5641884, 10406924, 19083836, 34802782, 63135539, 113965033, 204739662, 366156396, 652001918, 1156200929 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Terms 1, 2, 6, 15, 37, 85, ... are limits of diagonals in the triangle T(n, k)=A061260: 1 2, 1 3, 2, 1, 5, 6, 2, 1, 7, 11, 6, 2, 1, 11, 23, 15, 6, 2, 1, 15, 40, 32, 15, 6, 2, 1, 22, 73, 67, 37, 15, 6, 2, 1, 30, 120, 134, 79, 37, 15, 6, 2, 1, 42, 202, 255, 172, 85, 37, 15, 6, 2, 1, 56, 320, 470, 348, 187, 85, 37, 15, 6, 2, 1 LINKS FORMULA G.f.: Product_{k = 1..infinity} (1 - x^k)^( - numbpart(k + 1)), where numbpart(k) = number of partitions of k, cf. A000041. a(n) = 1/n*Sum_{k = 1..n} b(k)*a(n - k), n>0, a(0) = 1, where b(k) = Sum_{d|k} d*numbpart(d + 1). CROSSREFS Cf. A061260. Sequence in context: A017923 A018018 A030009 * A098790 A018019 A034518 Adjacent sequences:  A061258 A061259 A061260 * A061262 A061263 A061264 KEYWORD easy,nonn,changed AUTHOR Vladeta Jovovic, Apr 23 2001 STATUS approved

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