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 A364965 #7 Sep 01 2023 15:23:57 %S A364965 3,27,315,3003,42757,72765,195195,799425,13873275,18131225 %N A364965 Odd numbers k such that k is a multiple of A243071(k). %o A364965 (PARI) %o A364965 A243071(n) = if(n<=2, n-1, my(f=factor(n), p, p2=1, res=0); for(i=1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p*p2*(2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); ((3<<#binary(res\2))-res-1)); \\ (Combining programs given in A156552 and A054429) %o A364965 isA364965(n) = ((n>1)&&(n%2)&&!(n%A243071(n))); %Y A364965 Odd terms in A364964. %Y A364965 Sequence A163511(A364495(n)), for n>1, sorted into ascending order. %Y A364965 Cf. A243071. %Y A364965 Cf. also A364498, A364551. %K A364965 nonn,more %O A364965 1,1 %A A364965 _Antti Karttunen_, Sep 01 2023