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Numbers n with property that decimal expansion of 2^n+3^n contains no pair of neighbor equal digits (probably finite).
1

%I #4 Dec 09 2021 19:11:25

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

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

%e 2^73+3^73 = 67585198634826967968486182914745315.

%t Reap[Do[id=IntegerDigits[2^m+3^m];rm=Rest[id]-Most[id];If[FreeQ[rm,0],Sow[m]],{m,0,10000}]][[2,1]]

%t Select[Range[0,80],FreeQ[Differences[IntegerDigits[2^#+3^#]],0]&] (* _Harvey P. Dale_, Dec 09 2021 *)

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

%K base,fini,full,nonn

%O 0,3

%A _Zak Seidov_, Dec 11 2009