A171550 Numbers n with property that decimal expansion of 2^n+3^n contains no pair of neighbor equal digits (probably finite).

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 22, 23, 26, 27, 29, 45, 52, 73

Offset

0,3

Links

Table of n, a(n) for n=0..21.

Example

2^73+3^73 = 67585198634826967968486182914745315.

Mathematica

Reap[Do[id=IntegerDigits[2^m+3^m]; rm=Rest[id]-Most[id]; If[FreeQ[rm, 0], Sow[m]], {m, 0, 10000}]][[2, 1]]
Select[Range[0, 80], FreeQ[Differences[IntegerDigits[2^#+3^#]], 0]&] (* Harvey P. Dale, Dec 09 2021 *)

Crossrefs

Cf. A050723 (2^n), A050724 (3^n), A171551 (3^n-2^n).

Sequence in context: A366944 A289351 A362038 * A062895 A085869 A068892

Adjacent sequences: A171547 A171548 A171549 * A171551 A171552 A171553

Keyword

base,fini,full,nonn

Author

Zak Seidov, Dec 11 2009

Status

approved