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A358540
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a(n) is the smallest number with exactly n divisors that are n-gonal pyramidal numbers.
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3
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56, 140, 1440, 11550, 351120, 41580, 742560, 29279250, 8316000, 72348396120, 3386892600, 578918340
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OFFSET
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3,1
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COMMENTS
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Any subsequent terms are > 2 * 10^9. - Lucas A. Brown, Dec 24 2022
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LINKS
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Table of n, a(n) for n=3..14.
Lucas A. Brown, Python program.
Eric Weisstein's World of Mathematics, Pyramidal Number
Index entries for sequences related to divisors of numbers
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EXAMPLE
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a(5) = 1440 because 1440 has 5 pentagonal pyramidal divisors {1, 6, 18, 40, 288} and this is the smallest such number.
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CROSSREFS
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Cf. A005179, A358539, A358541, A358542, A358543.
Sequence in context: A044688 A241287 A201096 * A358860 A226128 A038850
Adjacent sequences: A358536 A358538 A358539 * A358541 A358542 A358543
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KEYWORD
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nonn,more
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AUTHOR
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Ilya Gutkovskiy, Nov 21 2022
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EXTENSIONS
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a(11)-a(13) from Martin Ehrenstein, Dec 02 2022
a(14) from Lucas A. Brown, Dec 19 2022
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STATUS
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approved
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