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 A171266 #6 Nov 14 2019 12:14:29 %S A171266 673,523777 %N A171266 Primes of the form 1 + triperfect numbers. %C A171266 A subsequence of A093034. %C A171266 If p is a term of this sequence then for each positive integer k, x=p^k %C A171266 is a solution for the equation sigma(phi(x))=3(x-1). See comment lines of %C A171266 the sequence A093034. %H A171266 Achim Flammenkamp, <a href="http://wwwhomes.uni-bielefeld.de/achim/mpn.html">The Multiply Perfect Numbers Page</a> %e A171266 p=673 is prime and sigma(p-1)/(p-1)=3, so p is in the sequence. %Y A171266 Cf. A005820, A093034, A171263, A171264, A171265. %K A171266 fini,full,nonn,bref %O A171266 1,1 %A A171266 _M. F. Hasler_ and _Farideh Firoozbakht_, Apr 15 2010