%I A124655
%S A124655 1,2,3,6,5,24,7,14,21,70,11,60,13,140,180,30,17,96,19,170,357,352,23,
%T A124655 132,105,494,75,336,29,840,31,62,924,850,1050,204,37,1064,1287,370,41,
%U A124655 1638,43,836,630,1564,47,276,301,470,2244,1170,53,312,2695,728,2793
%N A124655 a(n) = n-th integer from among those positive integers k where every
positive integers <= k and coprime to k is also coprime to n.
%H A124655 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a>
(listed in lieu of email address)
%e A124655 The positive integers k, where every positive integer <= k and coprime
to k is also coprime to 6, form the sequence 1,2,6,12,18,24,30,...
So a(6) is the 6th of these integers, which is 24. (3, for example,
is not among the sequence of k's because 2 is coprime to 3 and is
<= 3, but 2 is not coprime to 6.)
%t A124655 f[n_] := Select[Range[n], GCD[ #, n] == 1 &];g[n_] := Block[{k = 0, c
= n},While[c > 0,k++;While[Times @@ GCD[f[k], n] > 1, k++ ];c--;];
k];Table[g[n], {n, 60}] (*Chandler*)
%Y A124655 Sequence in context: A098012 A066117 A156833 this_sequence A066838 A084678
A102402
%Y A124655 Adjacent sequences: A124652 A124653 A124654 this_sequence A124656 A124657
A124658
%K A124655 nonn
%O A124655 1,2
%A A124655 Leroy Quet Dec 22 2006
%E A124655 Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Dec 24 2006
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