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%I #6 Mar 30 2012 18:39:11
%S 1,1,1,53,5,52,1,4,51,2,1,3,39,50,1,162,3,2,1,38,49,4,2,161,50,2,1,52,
%T 4,37,1,48,3,13,1,160,9,49,1,8,42,51,18,3,36,8,1,47,3,2,12,35,27,159,
%U 1,8,48,2,1,7,4,41,50,16,17,2,1,35,7,13,1,46,11,2,1,3,11,34,2,26,158,7,6,7
%N Start with n; iterate the process x -> ceiling(3x/2) until reach a prime. Sequence gives number of steps to reach a prime or 0 if no prime is ever reached.
%o (PARI) a(n)=if(n<0,0,s=n; c=1; while(isprime(ceil(3*s/2))==0,s=ceil(3*s/2); c++); c)
%Y Cf. A050412.
%K nonn
%O 1,4
%A _Benoit Cloitre_, Dec 17 2002