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A160422 Number of "ON" cells at n-th stage in simple 2-dimensional cellular automaton whose virtual skeleton is a polyedge as the toothpick structure of A139250 but with toothpicks of length 6. 8
0, 7, 19, 41, 63, 87, 131, 193, 235, 259, 303, 367, 435, 527, 675, 837, 919, 943, 987, 1051, 1119, 1211, 1359, 1523, 1631, 1723, 1875, 2071, 2299, 2631, 3087, 3489, 3651, 3675, 3719, 3783, 3851, 3943, 4091, 4255, 4363, 4455, 4607, 4803, 5031, 5363, 5819, 6223, 6411 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

a(n) is also the number of grid points that are covered after n-th stage by an polyedge as the toothpick structure of A139250, but with toothpicks of length 6.

LINKS

Table of n, a(n) for n=0..48.

David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.]

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

FORMULA

a(n) = A147614(n)+4*A139250(n) = A160420(n)+2*A139250(n) since each toothpick covers exactly four more grid points than the corresponding toothpick in A147614.

CROSSREFS

Cf. A139250, A139251, A147614, A160118, A160120, A160170, A160420, A160430.

Sequence in context: A191066 A087762 A195349 * A213782 A269428 A097240

Adjacent sequences: A160419 A160420 A160421 * A160423 A160424 A160425

KEYWORD

nonn

AUTHOR

Omar E. Pol, May 20 2009

EXTENSIONS

More terms and formula from Nathaniel Johnston, Nov 13 2010

STATUS

approved

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Last modified November 29 15:30 EST 2022. Contains 358431 sequences. (Running on oeis4.)