%I #45 Sep 16 2019 04:45:05
%S 1,7,3,2,5,15,21,4,6,9,11,14,13,49,35,8,17,51,19,10,30,33,23,12,20,25,
%T 27,18,29,87,31,16,22,77,85,42,37,133,39,26,28,41,43,86,45,63,47,24,
%U 56,175,75,34,53,159,55,44,38,57,59,70,61,217,93,32,40,65,67,119,46,69,71,36,73,259
%N a(n) is the smallest positive divisor not yet in the sequence of 7*A000217(n-1); n >= 1.
%C Up to n=10000, 1166 of the first 1228 odd primes appear as fixed points of a(n), i.e., 95%.
%C Conjecture: for large p prime, the odd primes (except p) appear as fixed points of b(n), where b(n) is the smallest positive divisor not yet in the sequence of p*A000217(n-1); n >= 1 (see link).
%H Enrique Navarrete and Daniel Orellana, <a href="http://arxiv.org/abs/1907.10023">Finding Prime Numbers as Fixed Points of Sequences</a>, arXiv:1907.10023 [math.NT], 2019.
%e For n = 1: a(1) = 1 is the smallest divisor of 7*0 not yet in the sequence.
%e For n = 23: a(23) = 23 is a fixed point and the smallest divisor of 7*253 not yet in the sequence.
%e For n = 73: a(73) = 73 is a fixed point and the smallest divisor of 7*2628 not yet in the sequence.
%Y Cf. A000217, A111273, A309275, A309276.
%K nonn
%O 1,2
%A _Enrique Navarrete_, Jul 27 2019
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