A045583 Numbers k that divide 10^k + 2^k.

1, 2, 3, 4, 8, 9, 16, 21, 26, 27, 32, 63, 64, 81, 128, 136, 147, 189, 243, 256, 338, 441, 512, 567, 609, 729, 903, 1024, 1029, 1252, 1323, 1378, 1701, 1827, 2048, 2187, 2312, 2667, 2709, 3087, 3969, 4096, 4263, 4394, 4401, 5103, 5481, 6321, 6561, 7203, 8001

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..1500

Crossrefs

Cf. A050621.

Programs

Mathematica

Select[Range[8100],Divisible[10^#+2^#,#]&]  (* Harvey P. Dale, Apr 02 2011 *)
Select[Range[8001], Divisible[PowerMod[2, #, #] + PowerMod[10, #, #], #] &] (* Amiram Eldar, Oct 23 2021 *)