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Similar to A080799 but count only addition steps.
3

%I #6 Oct 01 2013 17:57:35

%S 2,1,3,2,2,1,4,3,3,2,3,2,2,1,5,4,4,3,4,3,3,2,4,3,3,2,3,2,2,1,6,5,5,4,

%T 5,4,4,3,5,4,4,3,4,3,3,2,5,4,4,3,4,3,3,2,4,3,3,2,3,2,2,1,7,6,6,5,6,5,

%U 5,4,6,5,5,4,5,4,4,3,6,5,5,4,5,4,4,3,5,4,4,3,4,3,3,2,6,5,5,4,5,4,4,3,5,4,4

%N Similar to A080799 but count only addition steps.

%H Cino Hilliard, <a href="http://groups.msn.com/BC2LCC/page.msnw?fc_p=%2Fkx%2Bp%20problems&amp;fc_a=0">The x+1 conjecture</a>

%F a(n) = A008687(n+2) = A023416(n+1) + 1.

%o (PARI) xpcount2(n,p) = { for(x=1,n, p1 = x; f=0; ct=0; while(p1>1, if(p1%2==0,p1/=2; ct++,p1 = p1*p+1;); if(p1==7, p2=7; if(p2%2==0,p2/=2,p2 = p2*p+1); if(p2 ==8 && p1 ==7,f=1) ); ); if(f,print1(ct" ")) ) }

%K easy,nonn

%O 1,1

%A _Cino Hilliard_, Mar 25 2003