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%I #13 Oct 28 2020 03:57:22
%S 1,3,5,7,11,13,15,17,19,21,29,31,33,35,39,41,43,51,55,57,59,61,65,71,
%T 73,77,85,87,91,93,95,101,103,105,107,109,119,123,129,133,137,139,143,
%U 145,149,151,155,165,177,179,181,183,187,191,193,195,197,199
%N Numbers that are the product of distinct twin primes.
%H Robert Israel, <a href="/A334141/b334141.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TwinPrimes.html">Twin Primes</a>
%p N:= 1000: # for terms <= N
%p P:= select(isprime, {seq(i,i=3..N+2,2)}):
%p TP:= P intersect map(`+`,P,2):
%p TP:= map(t -> (t-2,t), TP):
%p TP:= sort(convert(TP,list)):
%p S:= {1}:
%p for i from 1 to nops(TP) do
%p S0:= S;
%p S:= S union map(`*`, select(`<=`,S,N/TP[i]),TP[i]);
%p od:
%p sort(convert(S,list)); # _Robert Israel_, Oct 28 2020
%Y Subsequence of A005117.
%Y Cf. A001097, A037074, A048599, A074480, A073485.
%K nonn
%O 1,2
%A _Ilya Gutkovskiy_, Apr 15 2020
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