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A044817
Positive integers having distinct base-6 run lengths.
17
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
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
KEYWORD
nonn,base
STATUS
approved