A045577 Numbers k that divide 4^k + 2^k or 8^k + 4^k.

1, 2, 3, 4, 8, 9, 10, 16, 27, 32, 50, 64, 68, 81, 128, 171, 243, 250, 256, 410, 512, 513, 729, 1024, 1156, 1250, 1539, 2048, 2050, 2056, 2187, 3249, 4096, 4617, 5050, 6250, 6561, 8192, 9747, 10250, 13203, 13851, 16384, 16810, 19652, 19683, 20512, 25250

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..500

Mathematica

Select[Range[30000], Divisible[4^#+2^#, #]||Divisible[8^#+4^#, #]&] (* Harvey P. Dale, Nov 24 2018 *)
Select[Range[30000], Divisible[PowerMod[2, #, #] + PowerMod[4, #, #], #] || Divisible[PowerMod[4, #, #] + PowerMod[8, #, #], #] &] (* Amiram Eldar, Oct 23 2021 *)

Crossrefs

Cf. A063481, A161168.

Sequence in context: A364381 A246444 A117847 * A111020 A002971 A157318

Adjacent sequences: A045574 A045575 A045576 * A045578 A045579 A045580

Keyword

nonn

Author

David W. Wilson

Status

approved