A266530 Partial sums of A266529.

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

Offset: 1

Author

Omar E. Pol, Jan 02 2016

Keywords

• nonn

Comments

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

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

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

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

Links

• Ivan Neretin, Table of n, a(n) for n = 1..8192
• N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS
• Index entries for sequences related to cellular automata

Crossrefs

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

Programs

Mathematica

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

Formula

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

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

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