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 A226105 #26 Jun 27 2025 21:43:23 %S A226105 1,195,5187,1141967133868035,3658018932844533311864835 %N A226105 Numbers k such that phi(k)+3 divides k+3, excluding numbers of the form 6*p for a prime p. %C A226105 Terms having (k+3)/(phi(k)+3) = 2 are shared with A350777. - _Max Alekseyev_, Oct 26 2023 %t A226105 Select[Range[10000000], !PrimeQ[#/6] && IntegerQ[(# + 3)/(EulerPhi[#] + 3)] &] %o A226105 (PARI) for(n=1,10^8, if( (n+3)%(eulerphi(n)+3)==0 && (n%6 || !isprime(n\6)), print(n))); %Y A226105 Set difference of A226104 and 6 * A000040. %Y A226105 Cf. A202855, A203966, A207575, A207667, A350777. %K A226105 nonn,hard,more %O A226105 1,2 %A A226105 _José María Grau Ribas_, May 26 2013 %E A226105 Edited and a(4)-a(5) added by _Max Alekseyev_, Nov 05 2023