A043278 Maximal run length in base 4 representation of n.

1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 2, 3, 2, 2, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 2, 2, 3, 2, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 2, 2, 2, 3, 3, 2, 2, 2, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 4, 3, 3, 2, 2, 2

Offset

1,5

Comments

Sequences A031942 (or A043090), A037977, A037978, A037979 list numbers for which a(n)=1, a(n)=2, a(n)=3, a(n)=4. - M. F. Hasler, Jul 23 2013

Links

Winston de Greef, Table of n, a(n) for n = 1..10000

Maple

mRunLen := proc(L)
    if nops(L) = 0 then
        0;
    else
        a := 1 ;
        for i from 2 to nops(L) do
            if op(i, L) = op(i-1, L) then
                a := a+1 ;
            else
                a := max(a, procname([op(i..nops(L), L)])) ;
                break;
            end if;
        end do:
        a ;
    end if ;
end proc:
A043278 := proc(n)
    convert(n, base, 4) ;
    mRunLen(%) ;
end proc: # R. J. Mathar, Jul 26 2015

Mathematica

Table[Max[Length/@Split[IntegerDigits[n, 4]]], {n, 100}] (* Harvey P. Dale, Jan 21 2014 *)

Prog

(PARI) A043278(n, b=4)={my(m, c=1); while(n>0, n%b==(n\=b)%b && c++ && next; m=max(m, c); c=1); m} \\ M. F. Hasler, Jul 23 2013

Crossrefs

Cf. A043276-A043290 for base-2 to base-16 analogs.

Sequence in context: A236833 A328511 A371245 * A125238 A380698 A025896

Adjacent sequences: A043275 A043276 A043277 * A043279 A043280 A043281

Keyword

nonn,base

Author

Clark Kimberling

Status

approved