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 A134713 #13 Oct 21 2024 04:35:44
%S A134713 1,1,2,3,8,11,12,23,52,79,96,115,508,593,1264,2187,2264,3199,4234,
%T A134713 4403,9668,9919,11190,19913,21676,23183,44470,86215,110474,132019,
%U A134713 216060,756807,859400,1257753,1398234,2976185,3021340,6972555,13466878
%N A134713 Base-2 logarithm of (n-th even superperfect number divided by 2^n), plus 1.
%H A134713 Amiram Eldar, <a href="/A134713/b134713.txt">Table of n, a(n) for n = 1..48</a>
%H A134713 Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>.
%F A134713 a(n) = 1 + log_2(A061652(n)/(2^n)) = A000043(n) - n = A090748(n) - n + 1.
%e A134713 a(5) = 8 because the 5th even superperfect number is 4096, 2^5 = 32, 4096/32 = 128, log_2(128) = 7 (because 2^7 = 128) and 7+1 = 8.
%t A134713 With[{max = 48}, MersennePrimeExponent[Range[max]] - Range[max]] (* _Amiram Eldar_, Oct 21 2024 *)
%Y A134713 Cf. A000043, A000396, A000668, A019279, A061652, A090748, A133028.
%K A134713 nonn
%O A134713 1,3
%A A134713 _Omar E. Pol_, Nov 07 2007