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A162777 a(n) = A153003(n) - A153006(n). 2
0, 0, 1, 1, 1, 3, 5, 3, 1, 3, 5, 5, 7, 13, 15, 7, 1, 3, 5, 5, 7, 13, 15, 9, 7, 13, 17, 19, 29, 43, 39, 15, 1, 3, 5, 5, 7, 13, 15, 9, 7, 13, 17, 19, 29, 43, 39, 17, 7, 13, 17, 19, 29, 43, 41, 27, 29, 45, 55, 69, 103, 127, 95, 31 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,6

COMMENTS

The main entry for this sequence is the toothpick sequence A139250.

LINKS

Jinyuan Wang, Rows n = 0..14 of triangle, flattened

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

Observation: It appears that a(2^i) = 1, i > 0 and a(2^i-1) = 2^(i-1) - 1, i > 0.

EXAMPLE

If written as a triangle:

0;

0;

1,1;

1,3,5,3;

1,3,5,5,7,13,15,7;

1,3,5,5,7,13,15,9,7,13,17,19,29,43,39,15;

...

Rows converge to A162779.

CROSSREFS

Cf. A139250, A152980, A153003, A153004, A153006, A162779.

Sequence in context: A243533 A239730 A287765 * A241014 A173454 A023505

Adjacent sequences:  A162774 A162775 A162776 * A162778 A162779 A162780

KEYWORD

nonn,tabf

AUTHOR

Omar E. Pol, Jul 23 2009

EXTENSIONS

More terms from Jinyuan Wang, Mar 15 2020

STATUS

approved

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Last modified December 2 05:01 EST 2021. Contains 349437 sequences. (Running on oeis4.)