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 A093708 #18 Apr 29 2024 09:08:58 %S A093708 0,9,200,2748,32041,351174,3729823,38917403,401729439,4117307658, %T A093708 41988266423,426654761185,4323703591195,43725896820062, %U A093708 441488068396967,4451827513629449,44843834524044694,451328767313095717 %N A093708 Number of odd nonprime differences of 2 (twin odd nonprimes) below 10^n. %C A093708 Count twin odd nonprimes below 10^n. %F A093708 a(n) = 10^n/2 - 2*A006880(n) + A007508(n) + 1. - _Max Alekseyev_, May 11 2005 %e A093708 a(2) = 9 because below 100 there are 9 twin odd nonprimes, e.g., 27 - 25 = 2. %Y A093708 Cf. A093683, A006880, A007508. %K A093708 nonn,more %O A093708 1,2 %A A093708 _Enoch Haga_, Apr 10 2004 %E A093708 More terms from _Max Alekseyev_, May 11 2005 %E A093708 a(16) corrected and a(17)-a(18) added using the data at A006880 and A007508 by _Amiram Eldar_, Apr 29 2024