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.
%I A100952 #12 Nov 16 2017 15:52:23
%S A100952 1,2,3,4,5,6,7,8,9,10,12,14,15,16,18,20,24,30,36,42,60
%N A100952 Numbers that cannot be written as p*q+r with three distinct primes p, q and r.
%C A100952 A100951(a(n)) = 0;
%C A100952 Conjecture: the sequence is complete.
%C A100952 A weaker conjecture: every integer greater than 60 (or some larger value based on further search) may be partitioned into a prime p and a semiprime qr, where the prime p is bounded by log(min(q,r)). Chen (1978) showed that all sufficiently large even numbers are the sum of a prime and the product of at most two primes. Zumkeller's conjecture effectively extends this from "even" to both even and odd integers. - _Jonathan Vos Post_, Nov 25 2004
%C A100952 Conjecture: Every positive integer can be represented as p*q-r with distinct primes p, q, r. - _Zak Seidov_, Aug 28 2012
%D A100952 Chen, J.-R. "On the Representation of a Large Even Number as the Sum of a Prime and the Product of at Most Two Primes, II." Sci. Sinica 21, 421-430, 1978.
%e A100952 A100949(60) = #{11+7*7, 5+5*11, 3+3*19, 2+2*29} = 4, but A100951(60) = 0 as in each partition only 2 primes are used, therefore 60 is a term.
%Y A100952 Cf. A100949, A100951.
%K A100952 nonn
%O A100952 1,2
%A A100952 _Reinhard Zumkeller_, Nov 23 2004