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%I #10 Feb 10 2014 03:29:21
%S 3,4,7,6,10,8,15,13,18,12,22,14,26,36,31,18,34,20,38,54,42,24,46,31,
%T 50,40,54,30,130,32,63,88,66,120,70,38,74,105,78,42,192,44,86,111,90,
%U 48,94,57,98,141,102,54,106,210,110,159,114,60,255,62,122,162
%N a(n) = n-th integer from among those positive integers which are each coprime to exactly one prime dividing n.
%e The positive integers which are each coprime to exactly one prime dividing 12 form the sequence: 2,3,4,8,9,10,14,15,16,20,21,22,26,27,28... The 12th of these is 22; so a(12) = 22.
%o (PARI) a(n) = {ok = 0; nb = 0; i = 1; pf = factor(n)[,1]; while(! ok, if (sum(j=1, #pf, gcd(i, pf[j]) == 1) == 1, nb++); if (nb == n, ok = 1, i++);); i;} \\ _Michel Marcus_, Feb 10 2014
%Y Cf. A125704, A128487.
%K nonn
%O 2,1
%A _Leroy Quet_, Mar 08 2007
%E Offset corrected and more terms from _Michel Marcus_, Feb 10 2014
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