A104321 - OEIS

%I #13 Aug 17 2024 22:51:11

%S 0,5,8,18,13,26,27,23,42,25,37,58,47,46,61,67,54,71,77,73,88,99,141,

%T 100,115,114,119,117,113,112,109,135,110,127,133,136,164,162,177,186,

%U 193,195,163,189,201,196,191,199,206,188,208,200,221,266,235,234,238,280

%N Smallest number m such that A104320(m)=n.

%C A104320(a(n))=n and A104320(m)<>n for m<a(n).

%C If it exists, a(115) > 10^5. - _Michel Marcus_, Oct 19 2016

%H Michel Marcus, <a href="/A104321/b104321.txt">Table of n, a(n) for n = 0..114</a>

%o (PARI) a(n) = {my(k = 0); while (#select(x->(x==0), digits(2^k, 3)) != n, k++); k;} \\ _Michel Marcus_, Oct 19 2016

%Y Cf. A036462, A060035, A104320, A375472.

%K nonn

%O 0,2

%A _Reinhard Zumkeller_, Mar 01 2005