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 A099982 #10 Oct 16 2024 09:19:43 %S A099982 2,5,13,19,61,107,521,1279,2281,4253,9689,11213,21701,44497,110503, %T A099982 216091,859433,1398269,3021377,13466917,24036583,30402457,37156667, %U A099982 43112609 %N A099982 Bisection of A000043. %F A099982 a(n) = A000043(2*n-1). - _Amiram Eldar_, Oct 16 2024 %t A099982 MersennePrimeExponent[Range[1, 48, 2]] (* _Amiram Eldar_, Oct 16 2024 *) %Y A099982 Cf. A000043, A099983. %K A099982 nonn,more %O A099982 1,1 %A A099982 _N. J. A. Sloane_, Nov 19 2004 %E A099982 Offset corrected and a(20)-a(24) added by _Amiram Eldar_, Oct 16 2024