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%I #24 Apr 06 2016 13:16:54
%S 1,3,5,7,9,13,15,19,21,25,31,33,37,39,43,45,55,61,63,73,75,91,99,109,
%T 111,115,121,133,141,145,151,153,163,165,181,183,187,199,201,205,211,
%U 213,217,225,271,273,295,301,309,313,315,361,381,385,421,423,433,435,451,463,465
%N Trajectory of 1 under the map n -> n + n/gpf(n) + 1 (see A269304).
%C _Cody M. Haderlie_ (see A269304) conjectures that the trajectory of any initial value will eventually merge with this sequence. The trajectory of 2, for example, begins 2, 4, 7, 9, 13, 15, 19, 21, 25, ... and from 7 on coincides with this sequence. See A271418.
%H Chai Wah Wu, <a href="/A270807/b270807.txt">Table of n, a(n) for n = 1..10000</a>
%o (Python)
%o from __future__ import division
%o from sympy import primefactors
%o A270807_list, b = [], 1
%o for i in range(10000):
%o A270807_list.append(b)
%o b += b//(max(primefactors(b)+[1])) + 1 # _Chai Wah Wu_, Apr 06 2016
%o (PARI) gpf(n) = if (n==1, 1, vecmax(factor(n)[,1]));
%o lista(nn) = {a = 1; for (n=1, nn, print1(a, ", "); a = a + a/gpf(a) + 1;);} \\ _Michel Marcus_, Apr 06 2016
%Y Cf. A006530, A269304, A271418.
%Y For first differences see A270808.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Apr 05 2016
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