%I #4 May 12 2018 17:21:38
%S 0,1,1,1,3,3,3,3,3,4,4,4,4,7,7,7,7,7,7,9,9,9,9,9,9,9,9,10,13,13,13,13,
%T 13,13,13,13,13,13,13,13,19,19,19,19,19,19,19,19,19,19,19,19,19,19,19,
%U 21,21,22,27,27,27,27,27,27,27,27,27,27,27,27,27,27
%N a(n+1) = 1 + min( 2*a(floor(n/2)), 3*a(floor(n/3)) ), with a(0) = 0.
%C Same recursion as Knuth numbers A007448 but different initial value.
%o (PARI) {a(n) = if( n<1, 0, n--; 1 + min( a(n\2)*2, a(n\3)*3 ))};
%Y Cf. A007448.
%K nonn
%O 0,5
%A _Michael Somos_, May 12 2018