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 A337797 Number of partitions of the n-th n-gonal pyramidal number into n-gonal pyramidal numbers. 4
 1, 1, 2, 4, 13, 45, 198, 858, 3728, 16115, 69125, 292940, 1224628, 5052396, 20570806, 82655098, 327881398, 1284663878, 4973614490, 19034194696, 72037124003, 269723590850, 999517370314, 3667158097572, 13325691939021, 47975192145998 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Eric Weisstein's World of Mathematics, Pyramidal Number FORMULA a(n) = [x^p(n,n)] Product_{k=1..n} 1 / (1 - x^p(n,k)), where p(n,k) = k * (k + 1) * (k * (n - 2) - n + 5) / 6 is the k-th n-gonal pyramidal number. EXAMPLE a(3) = 4 because the third tetrahedral (or triangular pyramidal) number is 10 and we have [10], [4, 4, 1, 1], [4, 1, 1, 1, 1, 1, 1] and [1, 1, 1, 1, 1, 1, 1, 1, 1, 1]. CROSSREFS Cf. A006484, A072964, A298269, A337762, A337798, A337799. Sequence in context: A193057 A115600 A007858 * A300931 A286074 A153930 Adjacent sequences:  A337794 A337795 A337796 * A337798 A337799 A337800 KEYWORD nonn AUTHOR Ilya Gutkovskiy, Sep 22 2020 STATUS approved

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Last modified August 7 23:16 EDT 2022. Contains 355995 sequences. (Running on oeis4.)