A299476 - OEIS

A299476

Toothpick sequence on triangular grid with word "abcb".

0, 1, 3, 7, 13, 21, 27, 39, 49, 57, 69, 87, 111, 135, 155, 185, 203, 211, 223, 241, 265, 293, 321, 367, 405, 453, 499, 567, 633, 701, 751, 823, 859, 869, 881, 899, 923, 951, 979, 1025, 1067, 1119, 1179, 1259, 1347, 1439, 1529, 1647, 1731, 1805

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

COMMENTS

a(n) gives the number of toothpicks of length 2 in the structure after n-th stage.

A299477 (the first differences) gives the number of toothpicks added at n-th stage.

For more information about the "word" of a cellular automaton see A296612.

LINKS

Table of n, a(n) for n=0..49.

N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS

Index entries for sequences related to cellular automata

Index entries for sequences related to toothpick sequences

CROSSREFS

Cf. A299477 (first differences), A296612.

Cf. A160120 (word "a"), A139250 (word "ab"), A296510 (word "abc"), A299478 (word "abcbc").

Sequence in context: A073896 A299478 A355310 * A077853 A256588 A025721

Adjacent sequences: A299473 A299474 A299475 * A299477 A299478 A299479

KEYWORD

nonn,more

AUTHOR

Omar E. Pol, Feb 11 2018

STATUS

approved