%I #13 Sep 16 2015 12:46:36
%S 0,1,3,5,11,13,13,15,15,17,29,41,41,43,29,53,47,49,43,41,67,43,47,67,
%T 49,61,53,79,69,83,103,67,67,69,99,87,79,91,79,97,93,83,145,87,95,133,
%U 93,95,143,145,101,161,155,173,167,191,167,197,191,175,131,199,153,159,159
%N a(0)=0, a(n) = the n-th positive integer that is coprime to (a(n-1)+1).
%H Vincenzo Librandi, <a href="/A130603/b130603.txt">Table of n, a(n) for n = 0..1000</a>
%e a(8) + 1 = 15 + 1 = 16. The positive integers which are coprime to 16 form the sequence: 1,3,5,7,9,11,13,15,17,19,21,23,... The 9th of these is 17. So a(9) = 17.
%t a = {0}; For[n = 1, n < 60, n++, i = 0; b = 0; While[i < n, b++; If[GCD[a[[ -1]] + 1, b] == 1, i++ ]]; AppendTo[a, b]]; a (* _Stefan Steinerberger_, Oct 16 2007 *)
%Y Cf. A123302.
%K nonn
%O 0,3
%A _Leroy Quet_, Aug 10 2007
%E More terms from _Stefan Steinerberger_, Oct 16 2007
%E More terms from _Sean A. Irvine_, Mar 03 2010
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