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 A106837 #9 Sep 14 2024 06:50:18
%S A106837 6,11,14,22,23,27,30,38,43,46,47,54,55,59,62,70,75,78,86,87,91,94,95,
%T A106837 102,107,110,111,118,119,123,126,134,139,142,150,151,155,158,166,171,
%U A106837 174,175,182,183,187,190,191,198,203,206,214,215,219,222,223,230
%N A106837 Numbers m such that both m and m+1 have odd part of the form 4*k+3.
%C A106837 The asymptotic density of this sequence is 1/4. - _Amiram Eldar_, Sep 14 2024
%H A106837 Harvey P. Dale, <a href="/A106837/b106837.txt">Table of n, a(n) for n = 1..1000</a>
%e A106837 30/2 = 15 == 3 (mod 4) and also 31 == 3 (mod 4), therefore 30 is in the sequence.
%t A106837 SequencePosition[Table[If[EvenQ[n],Mod[n/2^IntegerExponent[n,2],4], Mod[ n,4]],{n,250}],{3,3}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Nov 20 2016 *)
%Y A106837 Cf. A091067, A106838, A106840.
%Y A106837 Contains A106838 and A106838+1.
%K A106837 nonn
%O A106837 1,1
%A A106837 _Ralf Stephan_, May 03 2005