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 A333932 a(n) is the least integer that is 4-dimensional pyramidal in exactly n ways. 0
 5, 15, 35, 140, 1820, 11375, 820820, 19019000, 10790015600, 1568726956160, 7278234628665, 7271181889157550 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) has exactly n representations as an 4-dimensional pyramidal number P(m, k) = binomial(k + 2, 3)*(k*(m - 2) - m + 6) / 4, with m > 2, k > 1. LINKS Table of n, a(n) for n=1..12. Index to sequences related to pyramidal numbers EXAMPLE a(3) = 35 because 35 is the least integer which is 4-dimensional pyramidal in 3 ways (35 = P(3, 4) = P(7, 3) = P(33, 2)). CROSSREFS Cf. A063778, A080852, A261721, A333916. Sequence in context: A056413 A032276 A346890 * A065780 A220480 A105720 Adjacent sequences: A333929 A333930 A333931 * A333933 A333934 A333935 KEYWORD nonn,more AUTHOR Ilya Gutkovskiy, Apr 10 2020 EXTENSIONS a(9) from Giovanni Resta, Apr 11 2020 a(9) corrected and a(10)-a(12) from Bert Dobbelaere, Apr 14 2020 STATUS approved

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Last modified April 24 00:30 EDT 2024. Contains 371917 sequences. (Running on oeis4.)