A245318 - OEIS

A245318

Numbers k that divide 2^k + 5.

1, 7, 133, 1517, 11761, 676333, 1484413, 3627557, 10289371, 1449045241, 2433687407, 12309023183, 29013950411, 11701492535299, 223598572318157, 362232879754103

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

No other terms below 10^15. Some large terms: 37367159696063084325121, 1637537600494693555095121, 50692913747901869910332539, 407*(2^407+5)/1125038874668278099 (108 digits). - Max Alekseyev, Sep 22 2016

LINKS

Table of n, a(n) for n=1..16.

OEIS Wiki, 2^n mod n

EXAMPLE

2^7 + 5 = 133 is divisible by 7. Thus 7 is a term of this sequence.

MATHEMATICA

Select[Range[10^5], Divisible[2^# + 5, #] &] (* Robert Price, Oct 12 2018 *)

PROG

(PARI)

for(n=1, 10^9, if(Mod(2, n)^n==Mod(-5, n), print1(n, ", ")))

CROSSREFS

Cf. A128121, A168614.