A266530 - OEIS

%I #34 Feb 22 2023 21:42:35

%S 0,0,1,2,3,4,7,10,11,12,15,18,23,28,35,42,43,44,47,50,55,60,67,74,79,

%T 84,95,106,123,140,155,170,171,172,175,178,183,188,195,202,207,212,

%U 223,234,251,268,283,298,303,308,319,330,347,364,383,402,423,444,483,522,571,620,651,682,683,684,687,690,695,700

%N Partial sums of A266529.

%C Also the toothpick sequence A139250 and twice the terms of A255747 interleaved.

%C It appears that this sequence has a fractal (or fractal-like) behavior.

%C First differs from A266510 at a(55), with which it shares infinitely many terms.

%C First differs from A266540 at a(25), with which it shares infinitely many terms.

%H Ivan Neretin, <a href="/A266530/b266530.txt">Table of n, a(n) for n = 1..8192</a>

%H N. J. A. Sloane, <a href="/wiki/Catalog_of_Toothpick_and_CA_Sequences_in_OEIS">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a>

%H <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>

%F a(2n-1) = A139250(n).

%F a(2n) = 2 * A255747(n-1).

%F a(n) = (a(n-1) + a(n+1))/2, if n is an odd number greater than 1.

%t Accumulate[Riffle[#, #] &@ Nest[Join[#, 2 # + Append[Rest@#, 1]] &, {0}, 6]] (* _Ivan Neretin_, Feb 09 2017 *)

%Y Cf. A139250, A160552, A255747, A266510, A266529, A266540.

%K nonn

%O 1,4

%A _Omar E. Pol_, Jan 02 2016