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%I #11 Apr 09 2014 10:16:58
%S 1,2,1,3,2,6,2,7,1,10,3,10,4,8,7,15,7,18,6,13,9,22,8,20,8,19,9,28,6,
%T 29,11,22,11,26,10,34,13,25,11,40,10,42,16,24,15,45,13,43,12,31,18,50,
%U 16,42,19,38,23,57,12,58,24,38,24,46,18,65,24,43,15,68,19,71,28,37,26,66
%N A114652(n+1) - A114652(n).
%C First occurrence of n: 1, 2, 4, 13, a(5)=??, 6, 8, 14, 21, 10, 31, 49, 20, a(14)=??, 16, 43, a(17)=??, 18, 26, 24, ...,.
%e Among the first 5 terms of A114652 (1,2,4,5,8) there are 2 terms (1, 5) which are coprime to 6. So a(6) = 2.
%t a[1] = 1; a[n_] := a[n] = a[n - 1] + Count[GCD[Array[a, n - 1], n], 1]; b = Array[a, 80]; Drop[b, 1] - Drop[b, -1] (* _Robert G. Wilson v_ *)
%Y Cf. A114652.
%K nonn
%O 1,2
%A _Leroy Quet_, Dec 21 2005
%E Extended by _Ray Chandler_ and _Robert G. Wilson v_, Dec 23 2005
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