A246335 Second bisection of A246333.

1, 5, 9, 21, 25, 37, 57, 85, 89, 101, 121, 165, 169, 213, 217, 317, 321, 333, 353, 397, 401, 461, 481, 637, 593, 733, 689, 877, 801, 981, 921, 1157, 1185, 1197, 1217, 1261, 1265, 1325, 1345, 1501, 1457, 1613, 1585, 1829, 1721, 2037, 1913, 2381, 2145, 2477, 2409, 2685

Offset: 0

Author

N. J. A. Sloane, Aug 30 2014

Keywords

• nonn

Comments

a(2^k-1) begins 1,5,21,85, which is (4^k-1)/3, but a(15) = 317 not 341, breaking the pattern.

Links

• N. J. A. Sloane, Illustration of first 24 generations of A246333
• N. J. A. Sloane, Illustration of a(6) = 57 (Note that this is a different configuration of 57 cells from that in generation 6 of A169707, although the configurations of 37 cells at generation 5 are the same up to rotation.)
• N. J. A. Sloane, On the Number of ON Cells in Cellular Automata, arXiv:1503.01168, 2015
• Index entries for sequences related to cellular automata

Crossrefs

Cf. A246333, A246334, A247001. Similar to but different from A169707.

Programs

Mathematica

max = 100; (Partition[Total[Flatten[#]]& /@ CellularAutomaton[{493, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, max], 2] /. {a_, b_} -> {a, (max + 1 - Mod[max, 2])^2 - b} )[[All, 2]] (* Jean-François Alcover, Oct 03 2018 *)