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%I #5 Feb 22 2020 20:59:54
%S 0,1,2,1,2,3,2,3,5,1,2,3,2,3,5,3,4,7,2,3,5,3,4,7,5,6,13,1,2,3,2,3,5,3,
%T 4,7,2,3,5,3,4,7,5,6,13,3,4,7,4,5,11,7,8,19,2,3,5,3,4,7,5,6,13,3,4,7,
%U 4,5,11,7,8,19,5,6,13,6,7,17,13,14,43,1,2,3,2,3,5,3,4,7,2,3,5,3,4,7,5,6,13
%N Fixed point of the morphism a -> {a, a + 1, Prime(a + 1)}, beginning with 0.
%C First occurrence of k: 1, 2, 3, 6, 17, 9, 26, 18, 53, 158, 473, 51, 152, 27, 80, 239, 716, 78, 233, 54, 161, 482, 1445, 159, 476, 1427, ...,.
%t Nest[ Flatten[ #1 /. a_Integer -> {a, a + 1, Prime[a + 1]}] &, {0}, 5]
%K nonn
%O 0,3
%A _Robert G. Wilson v_, Aug 02 2006