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 A168145 #9 Apr 06 2018 17:41:17 %S A168145 1,5,6,12,18,24,36,42,48,60,84 %N A168145 Numbers n such that to abs(phi(n) - pi(n)) = 1. %C A168145 No more terms between 84 and 120000. - _R. J. Mathar_, Jun 04 2010 %F A168145 Solutions to A000010(x)=A000720(x)+k where k=+-1; finite for any fixed value of k. %e A168145 15 primes below 48=(2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47); 16 terms in RRS(48)=(1, 5, 7, 11, 13, 17, 19, 23, 25, 29, 31, 35, 37, 41, 43, 47), so 48 is here. %Y A168145 Cf. A000010, A000720, A037121, A037228, A073456. %K A168145 nonn %O A168145 1,2 %A A168145 _Juri-Stepan Gerasimov_, Nov 19 2009 %E A168145 Corrected (42 inserted) by _R. J. Mathar_, Jun 04 2010