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 A051066 #16 Jul 02 2025 16:01:58
%S A051066 0,1,1,1,2,2,2,3,3,4,4,5,6,6,7,8,8,9,9,10,10,10,11,11,11,12,12,12,13,
%T A051066 13,13,14,14,14,15,15,16,16,17,18,18,19,20,20,21,21,22,22,22,23,23,23,
%U A051066 24,24,24,25,25,25,26,26,26,27,27,28,28,29,30,30,31,32,32,33,33,34,34
%N A051066 Partial sums of A051065.
%D A051066 Letter from Gary W. Adamson concerning Prouhet-Thue-Morse sequence, Nov. 11, 1999.
%F A051066 a(n) = Sum_{k=0..n} A051065(k). - _Wesley Ivan Hurt_, May 25 2024
%t A051066 Accumulate[Join[{0}, Mod[Accumulate[Table[IntegerExponent[3*n, 3], {n, 1, 100}]], 2]]] (* _Amiram Eldar_, Jun 02 2025 *)
%Y A051066 Cf. A004128, A051065, A051067.
%K A051066 nonn,easy
%O A051066 0,5
%A A051066 _N. J. A. Sloane_ and _Gary W. Adamson_
%E A051066 More terms from _James Sellers_, Dec 11 1999