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 A110777 #20 Nov 21 2024 02:18:54 %S A110777 2,3,2,6,9,25,9,3,762,354,248,2181,606,1941,6423,11871 %N A110777 Number of digits in A110776(n). %o A110777 (Python) %o A110777 from sympy import isprime %o A110777 from itertools import count, islice %o A110777 def agen(): # generator of terms %o A110777 s = "" %o A110777 while True: %o A110777 for d in "17": %o A110777 for k in count(1): %o A110777 if isprime(int(s+d*k)): break %o A110777 yield k %o A110777 s += d*k %o A110777 print(list(islice(agen(), 11))) # _Michael S. Branicky_, Aug 23 2022 %Y A110777 Cf. A110774, A110775, A110776, A110778, A112534, A110780, A110781, A110782, A110783, A110788, A110789 %K A110777 base,nonn,more %O A110777 1,1 %A A110777 _Amarnath Murthy_, Aug 12 2005 %E A110777 a(7)-a(9) from _Joshua Zucker_, Jan 11 2006 %E A110777 a(10)-a(11) from _Sean A. Irvine_, Mar 22 2010 %E A110777 a(12)-a(14) from _Michael S. Branicky_, Aug 23 2022 %E A110777 a(15) from _Michael S. Branicky_, May 29 2023 %E A110777 a(16) from _Michael S. Branicky_, Nov 20 2024