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A245728 Numbers k that divide 2^k + 6. 3
1, 2, 10, 1030, 10009593662, 13957196317, 55299492770, 3764656723270 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

No other terms below 10^15. Some larger terms: 2962089521722084981, 1376243703434217460265762. - Max Alekseyev, Sep 23 2016

LINKS

Table of n, a(n) for n=1..8.

OEIS Wiki, 2^n mod n

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

Cf. A015910, A128122, A153972.

Sequence in context: A137890 A074333 A008559 * A171485 A291882 A215650

Adjacent sequences:  A245725 A245726 A245727 * A245729 A245730 A245731

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

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Last modified December 6 01:52 EST 2021. Contains 349558 sequences. (Running on oeis4.)