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 A152961 #18 Oct 20 2024 03:51:56
%S A152961 2,3,5,7,13,17,19,31,61,127,521,2281,3217,4253,9941,19937,21701,23209,
%T A152961 44497,110503,216091,859433,1257787,3021377,6972593,13466917,20996011,
%U A152961 30402457,32582657,42643801,57885161
%N A152961 Base-2 logarithm of A136007(n)+1.
%C A152961 The first 10 terms coincide with A109799.
%F A152961 a(n) = A000523(A136007(n)+1). - _Michel Marcus_, Apr 14 2021
%t A152961 q[n_] := n == 2 || Module[{d = Divisors[(n+1)/2]}, AllTrue[Range[3, Length[d]], d[[#]] >= 2 * d[[#-1]] &]]; Select[MersennePrimeExponent[Range[48]], q] (* _Amiram Eldar_, Oct 20 2024 *)
%Y A152961 Intersection of A000043 and A136002.
%Y A152961 Cf. A000523, A109799, A136003, A136005, A136007.
%K A152961 nonn,hard,more
%O A152961 1,1
%A A152961 _Omar E. Pol_, Dec 16 2008, Dec 20 2008
%E A152961 a(12)-(a31) from _Amiram Eldar_, Oct 20 2024