A031943 Numbers with no consecutive equal base-5 digits.

1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 20, 21, 22, 23, 26, 27, 28, 29, 35, 36, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 51, 52, 53, 54, 55, 57, 58, 59, 65, 66, 67, 69, 70, 71, 72, 73, 76, 77, 78, 79, 80, 82, 83, 84, 85, 86, 88

Offset

1,2

Links

Table of n, a(n) for n=1..63.

Formula

A031943 = { n | A043279(n)=1 } = A043091 \ {0}. - M. F. Hasler, Jul 23 2013

Mathematica

Select[Range[90], FreeQ[Differences[IntegerDigits[#, 5]], 0]&] (* Harvey P. Dale, Nov 30 2019 *)

Crossrefs

Cf. A000975 (base-2 analog), A031941 or A043089 (base-3 analog), A031942 or A043090 (base-4 analog), A043092, ..., A043096 (base-6 through base-10 analog).

Sequence in context: A204878 A037918 A043091 * A023800 A320340 A350838

Adjacent sequences: A031940 A031941 A031942 * A031944 A031945 A031946

Keyword

nonn,base

Author

Clark Kimberling

Status

approved