cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A115719 Products of two primes that are not Chen primes.

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%I A115719 #10 Jan 22 2025 05:25:20
%S A115719 1849,2623,3139,3397,3721,4171,4429,4453,4819,5329,5767,5917,6241,
%T A115719 6283,6493,7009,7081,7439,7519,7663,8137,8299,9211,9409,9589,9847,
%U A115719 9943,9991,10363,10553,10609,11023,11653,11773,11899,11911,11929,12169,12629,12877
%N A115719 Products of two primes that are not Chen primes.
%C A115719 Subset of semiprimes (A001358) such that neither prime factor is a Chen prime (A109611).
%e A115719 a(1) = 1849 = A102540(1)*A102540(1) = 43*43.
%e A115719 a(2) = 2623 = A102540(1)*A102540(2) = 43*61.
%e A115719 a(36) = 14701 = A102540(2)*A102540(13) = 61 * 241.
%Y A115719 Cf. A001358, A109611, A102540.
%K A115719 easy,nonn
%O A115719 1,1
%A A115719 _Jonathan Vos Post_, Mar 09 2006