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 A067886 #19 Sep 08 2022 08:45:05
%S A067886 2,3,6,9,11,14,15,18,21,23,27,29,33,42,47,51,53,54,57,69,71,73,74,81,
%T A067886 82,86,95,101,105,111,113,114,115,121,129,130,138,141,142,165,167,169,
%U A067886 179,181,199,203,209,213,230,233,235,243,250,255,258,277,279,306,307
%N A067886 Numbers k such that 2^k+1 and 2^k-1 have the same number of distinct prime factors.
%C A067886 Numbers k such that omega(2^k+1) = omega(2^k-1).
%H A067886 Amiram Eldar, <a href="/A067886/b067886.txt">Table of n, a(n) for n = 1..141</a>
%t A067886 sndpQ[n_]:=Module[{c=2^n},PrimeNu[c+1]==PrimeNu[c-1]]; Select[Range[ 250], sndpQ] (* _Harvey P. Dale_, Feb 04 2016 *)
%o A067886 (PARI) isok(k) = omega(2^k-1) == omega(2^k+1); \\ _Michel Marcus_, Feb 13 2020
%o A067886 (Magma) [k: k in [2..307] | #PrimeDivisors(2^k-1) eq #PrimeDivisors(2^k+1) ]; // _Marius A. Burtea_, Feb 13 2020
%Y A067886 Cf. A001221, A046799, A046800.
%K A067886 nonn
%O A067886 1,1
%A A067886 _Benoit Cloitre_, Mar 02 2002
%E A067886 More terms from _Rick L. Shepherd_, May 14 2002
%E A067886 More terms from _Amiram Eldar_, Feb 13 2020