OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
MAPLE
rlen := proc(n, ba) local rs, s, dgs, i ; rs :=0 ; s := 0; dgs := convert(n, base, ba) ; for i from 1 to nops(dgs) do if s = 0 then s :=1 ; else if op(i, dgs) <> op(i-1, dgs) then rs := rs+1 ; s :=1 ; else s :=s+1 ; fi; fi; od: rs := rs+1 ; RETURN (rs) ; end: for n from 1 to 200 do if rlen(n, 9) = 2 then printf("%d, ", n) ; fi; od: # R. J. Mathar, Oct 20 2008
MATHEMATICA
Select[Range[100], Length[Split[IntegerDigits[#, 9]]]==2&] (* Harvey P. Dale, Jan 06 2022 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
EXTENSIONS
Extended by R. J. Mathar, Oct 20 2008
STATUS
approved