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 A318572 K-th squarefree number such that A318411(k) is not equal to the largest prime factor of k-th squarefree number. 2
 35, 55, 70, 77, 95, 105, 110, 115, 119, 143, 154, 155, 161, 165, 187, 190, 203, 209, 210, 215, 221, 230, 231, 235, 238, 247, 253, 285, 286, 287, 295, 299, 310, 319, 322, 323, 329, 330, 335, 345, 355, 357, 371, 374, 377, 385, 391, 395, 403, 406, 407, 413, 415, 418, 429, 430 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Seiichi Manyama, Table of n, a(n) for n = 1..5000 EXAMPLE A005117(k) is k-th squarefree number. A073482(k) is the largest prime factor of A005117(k). A073482(k) = A318411(k) for 2 <= k <= 22. -------+------------+------------+------------     k  | A005117(k) | A073482(k) | A318411(k) -------+------------+------------+------------     23 |         35 |          7 |         13     34 |         55 |         11 |         21     44 |         70 |          7 |         13     48 |         77 |         11 |         31     60 |         95 |         19 |         37     65 |        105 |          7 |         13     69 |        110 |         11 |         21     73 |        115 |         23 |         45     75 |        119 |         17 |         49     89 |        143 |         13 |         61     94 |        154 |         11 |         31     95 |        155 |         31 |         61     99 |        161 |         23 |         67    101 |        165 |         11 |         21    115 |        187 |         17 |         81    116 |        190 |         19 |         37 PROG (Ruby) require 'prime' def A(n)   s = 1   flag = false   while !flag     s += 1     flag = true     (1..n - 1).each{|i|       if i != ((i ** s) % n)         flag = false         break       end     }   end   s end def A318572(n)   ary = []   i = 2   while ary.size < n     pq = i.prime_division     if pq.all?{|j| j[1] == 1}       ary << i if A(i) != pq[-1][0]     end     i += 1   end   ary end p A318572(50) CROSSREFS Cf. A005117, A073482, A318411. Sequence in context: A043135 A039312 A043915 * A171082 A121707 A267999 Adjacent sequences:  A318569 A318570 A318571 * A318573 A318574 A318575 KEYWORD nonn AUTHOR Seiichi Manyama, Aug 29 2018 STATUS approved

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Last modified April 7 01:11 EDT 2020. Contains 333291 sequences. (Running on oeis4.)