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%I #9 Dec 19 2015 13:17:36
%S 0,1,0,2,1,1,0,1,2,1,0,2,1,1,0,2,1,3,2,1,1,1,0,2,2,1,1,2,1,1,0,1,2,1,
%T 0,3,2,1,0,2,1,2,1,1,1,1,0,1,2,2,2,2,1,1,0,3,2,1,0,2,1,1,0,2,1,3,2,1,
%U 1,1,0,3,2,1,2,1,1,1,0,1,2,1,0,2,2,2,1,2,1,2,1,1,1,1,0,2,1,1,2,3,2,3,2
%N Start with n and reach 2 by repeatedly either dividing by d where d <= the square root or by adding 1. The division steps are free, but adding 1 costs 1 point. a(n) is the smallest cost to reach 2.
%Y Cf. A047988. Same formula except you cannot subtract 1 (only add).
%K nonn
%O 2,4
%A _Christian G. Bower_, May 15 1999
%E Edited by _Max Alekseyev_, Jun 13 2011