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A271471 Values k > 1 in A271328 such that k does not have any nontrivial divisors in A271328.

%I A271471 #15 Dec 10 2016 19:42:12
%S A271471 5,17,28,37,82,106,122,197,228,257,294,362,406,577,628,677,842,906,
%T A271471 1161,1228,1297,1376,1522,1606,1682,1937,2028,2117,2402,2513,2606,
%U A271471 2917,3028,3142,3482,3606,3722,4236,4357,4629,4762,4906,5042,5483,5777,6242,6406
%N A271471 Values k > 1 in A271328 such that k does not have any nontrivial divisors in A271328.
%C A271471 If k is in this sequence, then all multiples of k are in A271468.
%H A271471 Peter Kagey, <a href="/A271471/b271471.txt">Table of n, a(n) for n = 1..10000</a>
%e A271471 A271328(1) = 1 is not in this sequence because A271328(1) is not greater than 1.
%e A271471 A271328(2) = 5 is in this sequence because 5 does not have any nontrivial divisors.
%e A271471 A271328(3) = 10 is not in this sequence because A271328(2) is a proper divisor of A271328(3).
%e A271471 A271328(4) = 17 is in this sequence because 17 does not have any nontrivial divisors.
%e A271471 A271328(5) = 28 is in this sequence because 2, 4, 7, and 14 are not in A271328.
%t A271471 nn = 240; s = {1}; Do[AppendTo[s, Total@ Select[Range[n - 1], Divisible[n, s[[#]]] &]], {n, 2, nn}]; t = Table[s[[3 n]]/3, {n, nn/3}];
%t A271471 Select[Rest@ t, NoneTrue[Most@ Rest@ Divisors@ #, MemberQ[t, #] &] &] (* _Michael De Vlieger_, Apr 08 2016 *)
%K A271471 nonn
%O A271471 1,1
%A A271471 _Peter Kagey_, Apr 08 2016