A245318 Numbers k that divide 2^k + 5.

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

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.

Sequence in context: A051832 A103050 A110111 * A370782 A274788 A274258

Adjacent sequences: A245315 A245316 A245317 * A245319 A245320 A245321

Keyword

nonn,more

Author

Derek Orr, Jul 17 2014

Extensions

a(10)-a(13) from Lars Blomberg, Nov 05 2014

a(14)-a(16) from Max Alekseyev, Oct 09 2016

Status

approved