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 A377471 #41 Jan 29 2025 13:13:24 %S A377471 2,3,29,229,10273,1000099,1061069,101872769,1569793669,20207116829, %T A377471 1069666778189,102533896856389,10003581910211789,1000003754654504609, %U A377471 100003356331318330889 %N A377471 Smallest prime such that the number of distinct prime factors of its 9's complement is equal to n. If no such number exists return -1. %e A377471 2 is prime, 9-2 = 7 and omega(7) = 1; %o A377471 (PARI) nc(n) = my(e=length(Str(n))); 10^e-1 - n; \\ A061601 %o A377471 a(n) = my(p=2); while (omega(nc(p)) != n, p = nextprime(p+1)); p; \\ _Michel Marcus_, Jan 08 2025 %Y A377471 Cf. A000040, A001221, A061601, A378139. %K A377471 nonn,base,more %O A377471 1,1 %A A377471 _Jean-Marc Rebert_, Jan 08 2025 %E A377471 a(12)-a(15) from _Michael S. Branicky_, Jan 12 2025