A044817 Positive integers having distinct base-6 run lengths.

1, 2, 3, 4, 5, 7, 14, 21, 28, 35, 36, 42, 43, 44, 45, 46, 47, 50, 57, 64, 71, 72, 79, 84, 85, 86, 87, 88, 89, 93, 100, 107, 108, 115, 122, 126, 127, 128, 129, 130, 131, 136, 143, 144, 151, 158, 165, 168, 169, 170, 171, 172, 173, 179, 180, 187, 194, 201, 208, 210, 211

Offset

1,2

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

93 = 233_6 is in the sequence as it has distinct run lengths of same digits (1, 2). - David A. Corneth, Jan 04 2021

Maple

filter:= proc(n) local L, R, s, t, i;
  L:= convert(n, base, 6);
  R:= NULL; t:= 1; s:= L[1];
  for i from 2 to nops(L) do
    if L[i] <> s then
      R:= R, t; t:= 1; s:= L[i]
    else
      t:= t+1
    fi
  od;
  R:= R, t;
  nops([R]) = nops({R})
end proc:
select(filter, [$1..1000]); # Robert Israel, Jan 17 2018

Mathematica

A044817Q[k_] := DuplicateFreeQ[Map[Length, Split[IntegerDigits[k, 6]]]];
Select[Range[500], A044817Q] (* Paolo Xausa, Oct 26 2025 *)

Crossrefs

Cf. A044813, A044814, A044815, A044816, A044817, A044818, A044819, A044820, A044821, A044822, A044823, A044824, A044825, A044826, A044827 (base 2 to base 16).

Sequence in context: A092065 A044955 A297136 * A048303 A043709 A296700

Adjacent sequences: A044814 A044815 A044816 * A044818 A044819 A044820

Keyword

nonn,base

Author

Clark Kimberling

Status

approved