A050737 - OEIS

A050737

Numbers of form 7^k (values of k see A050728) containing no pair of consecutive equal digits (probably finite).

1, 7, 49, 343, 2401, 16807, 823543, 5764801, 40353607, 282475249, 13841287201, 232630513987207, 65712362363534280139543

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OFFSET

0,2

LINKS

MATHEMATICA

Select[7^Range[0, 200], !MemberQ[Differences[IntegerDigits[#]], 0]&] (* Vincenzo Librandi, Jan 22 2026 *)

PROG

(Magma) [7^n : n in [0..200] | not exists{i : i in [1..#d-1] | d[i+1] - d[i] eq 0} where d is Intseq(7^n) ]; // Vincenzo Librandi, Jan 22 2026

CROSSREFS

Subsequence of A000420.

KEYWORD

nonn,base

AUTHOR

STATUS

approved