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 A120380 Number of partitions of n*(n+1). 1
 1, 2, 11, 77, 627, 5604, 53174, 526823, 5392783, 56634173, 607163746, 6620830889, 73232243759, 819876908323, 9275102575355, 105882246722733, 1218374349844333, 14118662665280005, 164637479165761044, 1930656072350465812, 22755290216580025259, 269435605212954994471 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Henry Bottomley, Partition and composition calculator. G. P. Michon, Partition Function EXAMPLE a(2)=11 because the number of partitions of 6 is 11. MAPLE with(combinat); [seq(numbpart(n*(n+1)), n=1..20)]; with(combinat): seq(numbpart(n*(n+1)), n=0..21); PROG (PARI) a(n)=numbpart(n^2+n) /* Michael Somos, Jul 24 2006 */ CROSSREFS Cf. A003107, A002378. Sequence in context: A110329 A221844 A006766 * A079266 A094569 A151418 Adjacent sequences:  A120377 A120378 A120379 * A120381 A120382 A120383 KEYWORD nonn AUTHOR Zerinvary Lajos, Jun 29 2006 EXTENSIONS Edited by Michael Somos, Emeric Deutsch and N. J. A. Sloane, Jul 23 2006 STATUS approved

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Last modified June 16 21:55 EDT 2021. Contains 345080 sequences. (Running on oeis4.)