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A044819
Positive integers having distinct base-8 run lengths.
17
1, 2, 3, 4, 5, 6, 7, 9, 18, 27, 36, 45, 54, 63, 64, 72, 73, 74, 75, 76, 77, 78, 79, 82, 91, 100, 109, 118, 127, 128, 137, 144, 145, 146, 147, 148, 149, 150, 151, 155, 164, 173, 182, 191, 192, 201, 210, 216, 217, 218, 219, 220, 221, 222, 223, 228, 237, 246, 255, 256
OFFSET
1,2
LINKS
EXAMPLE
222 = 336_8 has a run length of two and a run length of 1, which are distinct lengths, so 222 is in the sequence. - R. J. Mathar, Jan 18 2018
MAPLE
rlset := proc(L::list)
local lset, rl, i ;
lset := [] ;
rl := 1 ;
for i from 2 to nops(L) do
if op(i, L) = op(i-1, L) then
rl := rl+1 ;
else
lset := [op(lset), rl] ;
rl := 1;
end if;
end do:
lset := [op(lset), rl] ;
end proc:
isA044819 := proc(n)
local dgs, rl;
dgs := convert(n, base, 8) ;
rl := rlset(dgs) ;
if nops(rl) = nops( convert(rl, set)) then
true;
else
false;
end if;
end proc:
for n from 1 to 400 do
if isA044819(n) then
printf("%d, ", n) ;
end if;
end do: # R. J. Mathar, Jan 18 2018
KEYWORD
nonn,base
STATUS
approved