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 A289554 #18 Jul 02 2025 19:24:03 %S A289554 24,32,36,40,48,54,56,60,64,72,80,84,88,90,96,100,104,108,112,120,126, %T A289554 128,132,135,136,140,144,150,152,156,160,162,168,176,180,184,189,192, %U A289554 196,198,200,204,208,210,216,220,224,225,228,232,234,240,243,248,250 %N A289554 Numbers that are the product of two distinct composite numbers (A002808). %e A289554 Number 24 is in the sequence because 24 = 4 * 6. %o A289554 (Magma) [n: n in [1..1000] | (#PrimeDivisors(n) eq 1 and NumberOfDivisors(n) ge 6) or (#PrimeDivisors(n) eq 2 and NumberOfDivisors(n) ge 8) or (#PrimeDivisors(n) ge 3 and NumberOfDivisors(n) ge 12) or (#PrimeDivisors(n) ge 4)]; %Y A289554 Complement of A289555. %Y A289554 Cf. A006881 (with two distinct primes), A002808 (with two distinct nonprimes), A167171 (with two distinct noncomposites). %K A289554 nonn %O A289554 1,1 %A A289554 _Jaroslav Krizek_, Jul 07 2017