

A152617


Smallest number m such that m has exactly n distinct prime factors and sigma(m) has exactly n distinct prime factors.


0



2, 6, 60, 1140, 22230, 778050, 28787850, 1237877550, 82937795850, 6054459097050, 802693813972050, 126022928793611850
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OFFSET

1,1


COMMENTS

a(13) <= 20541737393358731550. a(14) <= 3553720569051060558150.  Donovan Johnson, Jul 13 2011


LINKS



EXAMPLE

a(9) = 82937795850 = 2*3^2*5^2*7*13*19*37*43*67 (9 distinct prime factors). Sigma(82937795850) = 307906959360 = 2^11*3*5*7*11*13*17*19*31 (9 distinct prime factors).


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



