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 A077646 #10 Mar 18 2018 04:03:51 %S A077646 45,63,75,90,99,117,120,126,147,150,153,168,171,198,207,216,234,243, %T A077646 261,264,279,280,294,306,312,333,342,363,369,387,405,408,414,420,423, %U A077646 440,456,477,486,507,520,522,531,540,549,552,558,603,616,639,657,660 %N A077646 Solutions to lcm(n, tau(n)) = 2n which are neither prime nor twice a prime, where tau(k) = d(k) is the number of divisors of k. %H A077646 Charles R Greathouse IV, <a href="/A077646/b077646.txt">Table of n, a(n) for n = 1..10000</a> %F A077646 Composite solutions to A009530(x)=2x which are not twice a prime. %e A077646 n=63: d(n) = tau(n) = 6, lcm(63,6) = 126 = 2n. %o A077646 (PARI) is(n)=!isprime(if(n%2,n,n/2)) && lcm(n,numdiv(n))==2*n \\ _Charles R Greathouse IV_, Oct 28 2013 %Y A077646 Cf. A009530, A001747, A000040, A065091. %K A077646 nonn %O A077646 1,1 %A A077646 _Labos Elemer_, Nov 18 2002