%I A018845
%S A018845 1,4,2,3,2,1,2,2,2,1,3,1,2,1,1,3,2,2,2,1,1,2,2,2,2,1,3,3,2,3,5,4,1,1,1,
%T A018845 2,2,1,2,2,10,3,2,1,6,1,3,1,5,5,1,5,3,2,1,2,4,2,2,4,3,4,3,4,13,13,3,4,
%U A018845 3,4,3,3,3,4,12
%N A018845 Number of iterations required for the sum of n and its prime divisors
= t to reach a prime (where t replaces n in each iteration) in A016837.
%F A018845 Factor n, add n and its prime divisors. Sum = t, t replaces n, repeat
until a prime is produced in k iterations.
%e A018845 a(4)=4. 4=2*2, so 4+2+2=8. 8=2*2*2 so 8+2+2+2=14. 14=2*7 so 14+2+7=23,
prime in 3 iterations.
%Y A018845 Sequence in context: A145326 A016513 A063447 this_sequence A028947 A068152
A079636
%Y A018845 Adjacent sequences: A018842 A018843 A018844 this_sequence A018846 A018847
A018848
%K A018845 easy,nonn
%O A018845 1,2
%A A018845 Enoch Haga, Carlos B. Rivera F., Patrick De Geest (Enokh(AT)comcast.net,
crivera(AT)ux1.sci.net.mx, pdg(AT)worldofnumbers.com)
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