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 A119317 n-th divisor of A087134(n), the smallest number whose n-th divisor is prime (for n > 1). 3
 1, 2, 3, 5, 7, 7, 13, 13, 19, 17, 23, 31, 29, 31, 41, 61, 61, 61, 47, 61, 73, 97, 127, 71, 97, 107, 127, 149, 173, 211, 127, 97, 107, 211, 127, 149, 173, 181, 211, 257, 281, 317, 181, 421, 241, 257, 281, 317, 337, 367, 421, 509, 563, 631, 727, 421, 487, 509 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 MATHEMATICA 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 *) PROG (Maxima) A119317(n) := block(    if equal(n, 1) then       return(1),    for i : 1 do (       idv : listify(divisors(i)),       if length(idv) >= n then (          if primep(idv[n]) then             return(idv[n])         )      ) )\$ /* R. J. Mathar, Mar 13 2012 */ CROSSREFS Cf. A000040, A119318, A119319. Sequence in context: A270176 A064142 A067792 * A198424 A337139 A039248 Adjacent sequences:  A119314 A119315 A119316 * A119318 A119319 A119320 KEYWORD nonn AUTHOR Reinhard Zumkeller, May 15 2006 EXTENSIONS More terms from Amiram Eldar, Feb 06 2019 STATUS approved

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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)