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%I #15 Feb 16 2019 21:10:30
%S 1,2,3,5,7,7,13,13,19,17,23,31,29,31,41,61,61,61,47,61,73,97,127,71,
%T 97,107,127,149,173,211,127,97,107,211,127,149,173,181,211,257,281,
%U 317,181,421,241,257,281,317,337,367,421,509,563,631,727,421,487,509
%N n-th divisor of A087134(n), the smallest number whose n-th divisor is prime (for n > 1).
%H Amiram Eldar, <a href="/A119317/b119317.txt">Table of n, a(n) for n = 1..10000</a>
%t a[1] = 1; a[n_] := Module[{k = 1, d}, While[DivisorSigma[0, k] < n || ! PrimeQ[d = Divisors[k][[n]]], k++]; d]; Array[a, 30] (* _Amiram Eldar_, Feb 06 2019 *)
%o (Maxima) A119317(n) := block(
%o if equal(n,1) then
%o return(1),
%o for i : 1 do (
%o idv : listify(divisors(i)),
%o if length(idv) >= n then (
%o if primep(idv[n]) then
%o return(idv[n])
%o )
%o )
%o )$ /* _R. J. Mathar_, Mar 13 2012 */
%Y Cf. A000040, A119318, A119319.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, May 15 2006
%E More terms from _Amiram Eldar_, Feb 06 2019
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