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%I #9 Apr 04 2014 01:50:15
%S 1,2,4,6,10,8,14,18,12,16,26,22,34,28,20,28,44,38,56,48,36,46,24,32,
%T 52,40,58,70,42,50,80,64,84,68,92,104,140,122,98,82,122,110,152,132,
%U 108,86,132,116,74,54,86,62,114,96,136,112,76,104,162,146,206,176,212,180,228
%N Recamán variation: a(1) = 1; for n > 1, a(n) = a(n-1)-f(n) if that number is positive and not already in the sequence, otherwise a(n) = a(n-1)+f(n), where f(n)=phi(n) (cf. A000010).
%Y Cf. A005132, A079051, A000010, A079053.
%K nonn
%O 1,2
%A _Benoit Cloitre_, Feb 02 2003