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 A078151 #6 Jun 18 2025 23:19:01 %S A078151 240,120,960,6528,4080,1920,15360,24960,61440,13440,16320,87360, %T A078151 983040,196560,1432080,130560,861840,32640,98280,114240,2545920, %U A078151 293760,261120,967680,174720,2673216,4194240,1081080,1044480,913920,1659840,424320 %N A078151 Smallest k such that d(phi(k)) - phi(d(k)) = -n, where d(k) = A000005(k) and phi(k) = A000010(k). %e A078151 a(77)=2970240, since d(phi(2970240)) - phi(d(2970240)) = -77 first appears here; while d(phi(x)) - phi(d(x)) takes large positive values,absolute value of negative differences grows significantly slower. %Y A078151 Cf. A000005, A000010, A078150. %Y A078151 Least inverse of -A385122. %K A078151 easy,nonn %O A078151 1,1 %A A078151 _Labos Elemer_, Nov 26 2002