

A309542


Numbers k such that A001414(k^3+1) is divisible by k.


2



1, 2, 5, 7, 20, 24, 45, 54, 286, 1942, 30771000, 71149819, 106438598, 668274063
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OFFSET

1,2


COMMENTS

a(15) > 1.5*10^9.  Giovanni Resta, Aug 07 2019


LINKS

Table of n, a(n) for n=1..14.


EXAMPLE

5 is a member because the prime factorization of 5^3+1=126 is 2*3^2*7 and 2+3+3+7=15 is divisible by 5.


MAPLE

filter:= proc(n) local F, t;
F:= ifactors(n^3+1)[2];
add(t[1]*t[2], t=F) mod n = 0
end proc:
select(f, [$1..10000]);


CROSSREFS

Cf. A001414, A309534, A309544.
Sequence in context: A096146 A041583 A143915 * A327322 A160820 A158357
Adjacent sequences: A309539 A309540 A309541 * A309543 A309544 A309545


KEYWORD

nonn,more


AUTHOR

J. M. Bergot and Robert Israel, Aug 06 2019


EXTENSIONS

a(11)a(14) from Giovanni Resta, Aug 07 2019


STATUS

approved



