%I #13 Jan 15 2024 18:44:16
%S 2,7,11,15,21,26,31,35,39,44,50,56,62,67,71,75,81,86,91,95,99,104,110,
%T 116,122,127,131,135,141,146,151,155,159,164,170,176,182,187,191,195,
%U 201,206,211,215,219,224,230,236,242,247,251,255,261,266,271,275,279,284,290,296
%N Trajectory of 2 under repeated application of the map: n -> n + third-smallest number that does not divide n.
%H Harvey P. Dale, <a href="/A140491/b140491.txt">Table of n, a(n) for n = 1..1000</a>
%t NestList[Complement[Range[3+#],Divisors[#]][[3]]+#&,2,60] (* _Harvey P. Dale_, Jan 15 2024 *)
%o (PARI) third(n) = {my(nb = 0, k = 1); while (nb != 3, if (n % k, nb++); if (nb != 3, k++);); k;}
%o f(n) = n + third(n);
%o lista2(nn) = {a = 2; print1(a, ", "); for (n=2, nn, newa = f(a); print1(newa, ", "); a = f(a););} \\ _Michel Marcus_, Oct 04 2018
%Y Cf. A140485, A140486, A140487, A140488, A140489 (second-smallest sequences).
%Y Cf. A140490, A140492, A140493, A140494 (third-smallest sequences).
%K nonn
%O 1,1
%A _Jacques Tramu_, Jun 25 2008
%E More terms from _Michel Marcus_, Oct 04 2018
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