A031941 Numbers without consecutive equal base 3 digits.

1, 2, 3, 5, 6, 7, 10, 11, 15, 16, 19, 20, 21, 23, 30, 32, 33, 34, 46, 47, 48, 50, 57, 59, 60, 61, 64, 65, 69, 70, 91, 92, 96, 97, 100, 101, 102, 104, 138, 140, 141, 142, 145, 146, 150, 151, 172, 173, 177, 178, 181, 182, 183, 185, 192

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• base

Comments

Essentially the same as A043089, b.t.w. the initial "0" could be as well included here. Also: numbers n such that A043277(n)=1. - M. F. Hasler, Jul 23 2013

Crossrefs

Cf. A000975 (base-2 analog), A031942 or A043090 (base-4 analog), A031943 or A043091 (base-5 analog), A043092, ..., A043096 (base-6 through base-10 analog).

Programs

Mathematica

Select[Range[200],FreeQ[Differences[IntegerDigits[#,3]],0]&] (* Harvey P. Dale, Mar 03 2024 *)

PARI

for(i=1,199,A043277(i)==1 & print1(i",")) \\ - M. F. Hasler, Jul 23 2013

Formula

A031941 = { n | A043277(n)=1 } = A043089 \ {0}. - M. F. Hasler, Jul 23 2013

Extensions

Edited by Charles R Greathouse IV, Aug 02 2010