

A071147


Smallest squarefree number k with exactly n prime factors such that the sum of the prime factors is divisible by the largest prime dividing k, or 0 if no such k exists.


8



1, 2, 0, 30, 3135, 3570, 72930, 1231230, 14804790, 497668710, 14908423530, 278196808890, 12192694624110, 550939666387110, 21275256232500270, 1458502323630662310, 87988283090327810190, 3254611619240885033130, 261462818462495728868790, 9965666894849284108299810, 557940830126698960967415390, 90544636506979071680577724410
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OFFSET

0,2


COMMENTS

No solution exists for n=2, so a(2)=0.


LINKS



FORMULA

A008472(k)/A006530(k) is an integer; k is squarefree and has exactly n prime factors.


EXAMPLE

a(0) = 1 = 1;
a(1) = 2 = 2;
a(3) = 30 = 2 * 3 * 5;
a(4) = 3135 = 3 * 5 * 11 * 19;
a(5) = 3570 = 2 * 3 * 5 * 7 * 17;
a(6) = 72930 = 2 * 3 * 5 * 11 * 13 * 17;
a(7) = 1231230 = 2 * 3 * 5 * 7 * 11 * 13 * 41.


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



