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 A161974 #16 Jun 22 2024 00:43:54 %S A161974 1,2,1,2,1,1,1,1,1,2,1,2,1,2,1,2,1,2,1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,2, %T A161974 1,2,1,1,1,1,1,2,1,2,1,2,1,2,1,2,1,2,1,1,1,1,1,2,1,2,1,2,1,2,1,2,1,2, %U A161974 1,1,1,1,1,2,1,2,1,2,1,2,1,2,1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,2,1,2,1 %N A161974 a(n) = number of equalities of the form A010060(n+k) = A010060(n), k=1,2,3. %C A161974 See comment to A161916. 3-a(n) is the number of equalities of kind A010060(n+k) = 1-A010060(n), k=1,2,3. %o A161974 (PARI) a(n)=sum(k=1,3,hammingweight(n)%2==hammingweight(n+k)%2) \\ _Charles R Greathouse IV_, Aug 20 2013 %Y A161974 Cf. A161916, A161890, A161824, A161817, A161674, A161673, A161639, A161641, A161627, A161579, A161580, A121539, A131323, A036554, A010060. %K A161974 nonn,easy %O A161974 0,2 %A A161974 _Vladimir Shevelev_, Jun 23 2009 %E A161974 Missing a(24)=1 inserted by _Georg Fischer_, Jun 21 2024