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%I #9 Aug 27 2019 17:49:24
%S 1,3,5,7,11,17,25,28,34,38,39,41,46,48,53,57,68,72,73,77,80,91,100,
%T 108,110,113,115,116,120,123,128,135,144,156,161,175,185,189,198,202,
%U 205,217,224,231,235,245,247,252,255,267,273,275,276,278,285,297,301,304,315,320,324
%N Positions of primes in A003072.
%H Robert Israel, <a href="/A024967/b024967.txt">Table of n, a(n) for n = 1..8446</a>
%p N:= 10000: # for members of A003072 up to N
%p S:= {}:
%p for x from 1 while 3*x^3 <= N do
%p for y from x while x^3+2*y^3<=N do
%p for z from y do
%p v:= x^3+y^3+z^3;
%p if v > N then break fi;
%p S:= S union {v}
%p od od od:
%p S:= sort(convert(S,list)):
%p select(i -> isprime(S[i]),[$1..nops(S)]); # _Robert Israel_, Aug 27 2019
%K nonn
%O 1,2
%A _Clark Kimberling_
%E More terms from _Sean A. Irvine_, Jul 30 2019
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