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 A116000 #4 Feb 05 2013 18:01:18 %S A116000 2,3,4,5,6,7,10,11,13,16,17,19,22,23,25,27,29,31,37,40,41,43,46,47,52, %T A116000 53,58,59,61,64,67,68,71,72,73,79,80,82,83,89,97,98,101,103,106,107, %U A116000 109,113,117,127,128,131,136,137,139,144,149,151,157,162,163,166,167 %N A116000 phi(n) + sigma(n) gives a semiprime (A001358). %e A116000 phi(101)+sigma(101)=202=2*101. %t A116000 Select[Range[200],PrimeOmega[EulerPhi[#]+DivisorSigma[1,#]]==2&] (* _Harvey P. Dale_, Feb 05 2013 *) %Y A116000 Cf. A001358, A116016, A116001. %K A116000 nonn %O A116000 1,1 %A A116000 _Giovanni Resta_, Feb 13 2006