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A156237 Smallest hexagonal number with n distinct prime factors. +0
4
6, 66, 630, 7140, 103740, 1272810, 56812470, 1722580860, 48098217090, 1850186768430, 139261952960130, 17743036637876550, 741902728913225880, 21549201398378163510, 2378522762792139793830, 351206814022419685159830 (list; graph; listen)
OFFSET

2,1
LINKS

Eric Weisstein's World of Mathematics, Hexagonal Numbers.

EXAMPLE

a(9) = 1722580860 = 2^2*3*5*7*11*13*23*29*43. 1722580860 is the smallest hexagonal number with 9 distinct prime factors.

CROSSREFS

Cf. A000384, A076551, A156236, A156238, A156239.

Sequence in context: A119214 A075138 A043041 this_sequence A119142 A119091 A119100

Adjacent sequences: A156234 A156235 A156236 this_sequence A156238 A156239 A156240

KEYWORD

nonn

AUTHOR

Donovan Johnson (donovan.johnson(AT)yahoo.com), Feb 07 2009

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.

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