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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

David A. Corneth, Table of n, a(n) for n = 1..10000

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

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: A083376 A044957 A297142 * A048305 A043711 A296706

Adjacent sequences:  A044816 A044817 A044818 * A044820 A044821 A044822

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified January 20 21:46 EST 2022. Contains 350472 sequences. (Running on oeis4.)