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 A237798 #11 Jul 14 2021 08:49:08 %S A237798 750,5022,8037,18250,60249,105669,1760490,1965270,4626489,62546070, %T A237798 202631245,441416073,286952692809 %N A237798 Numbers k such that phi(k) equals the product of two numbers: sums of prime factors of k, with and without repetition. %C A237798 25446095286407049 and 27093686218810118911929 are terms. %e A237798 750 = 2*3*5^3 is a term since phi(750) = 200 = (2+3+5) * (2+3+5+5+5). %t A237798 Select[Range[2, 10^5], (f=FactorInteger@#; EulerPhi[#] == Total[First /@ f]* Total[Times @@@ f]) &] %Y A237798 Cf. A000010, A001414, A008472, A073396. %K A237798 nonn %O A237798 1,1 %A A237798 _Giovanni Resta_, Feb 13 2014