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%I #6 Sep 24 2013 00:41:42
%S 21,22,28,29,33,38,53
%N Numbers that appear in the successive application of the sequence A125736 (sum of the neighbors integer-log).
%C There are two cycles (28 38 53) and (21 22 33 29), that are the attractors in this fixed point iteration.
%e nilog(28)=ilog(27)+ilog(29)=ilog(3^3)+ilog(29)=3*3+29=38.
%e nilog(38)=ilog(37)+ilog(39)=ilog(37)+ilog(13*3)=37+(13+3)=53.
%e nilog(53)=ilog(52)+ilog(54)=ilog(2^2*13)+ilog(2*3^3)=(2*2+13)+(2+3*3)=28.
%t f[n_] := Plus @@ Times @@@ FactorInteger@ n; f[1] = 0; g[n_] := f[n - 1] + f[n + 1]; Union[ Nest[g, #, 31] & /@ Range[3, 500000]]
%K fini,nonn
%O 0,1
%A _Carlos Alves_, Dec 02 2006
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