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A245728
Numbers k that divide 2^k + 6.
4
1, 2, 10, 1030, 10009593662, 13957196317, 55299492770, 3764656723270
OFFSET
1,2
COMMENTS
No other terms below 10^15. Some larger terms: 2962089521722084981, 1376243703434217460265762. - Max Alekseyev, Sep 23 2016
EXAMPLE
2^10 + 6 = 1030 is divisible by 10. Thus 10 is a term of this sequence.
MAPLE
select(n -> 2 &^ n + 6 mod n = 0, [$1..10^6]); # Robert Israel, Jul 30 2014
MATHEMATICA
Select[Range[10^5], Divisible[2^# + 6, #] &] (* Robert Price, Oct 12 2018 *)
PROG
(PARI)
for(n=1, 10^9, if(Mod(2, n)^n==Mod(-6, n), print1(n, ", ")))
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
Derek Orr, Jul 30 2014
EXTENSIONS
a(5) from Jason G. Wurtzel, Sep 25 2014
a(6)-a(8) from Max Alekseyev, Sep 23 2016
STATUS
approved