cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A266532 Total number of Y-toothpicks after n-th stage in the "outward" version of the cellular automaton of A160120.

Original entry on oeis.org

0, 1, 4, 7, 16, 19, 28, 37, 58, 61, 70, 79, 100, 109, 130, 151, 196, 199, 208, 217, 238, 247, 268, 289, 334, 343, 364, 385, 430, 451, 496, 541, 634, 637, 646, 655, 676, 685, 706, 727, 772, 781, 802, 823, 868, 889, 934, 979, 1072, 1081, 1102, 1123, 1168, 1189, 1234, 1279, 1372, 1393, 1438, 1483, 1576, 1621, 1714, 1807, 1996, 1999, 2008, 2017
Offset: 0

Views

Author

David Applegate and Omar E. Pol, Jan 18 2016

Keywords

Comments

For the connection with A160720 (the "outward" version of the Ulam-Warburton cellular automaton A147562) see formula section and A267700.
A266533 (the first differences) gives the number of Y-toothpicks added to the structure at n-th stage.
First differs from A160120 at a(9).
First differs from A160715 at a(13).

Links

Crossrefs

Cf. A139250, A147562, A159912, A160120, A160715, A160720, A266533, A267700, A267701.

Formula

Conjecture: a(n) = 1 + 3*(A160720(n) - 1)/4 = 1 + 3*A267700(n-1), n >= 1. This formula is correct! - N. J. A. Sloane, Jan 23 2016
a(n) = 1 + 3*(A159912(n) - n)/2, n >= 1. - Omar E. Pol, Jan 24 2016

A266533 First differences of A266532.

Original entry on oeis.org

1, 3, 3, 9, 3, 9, 9, 21, 3, 9, 9, 21, 9, 21, 21, 45, 3, 9, 9, 21, 9, 21, 21, 45, 9, 21, 21, 45, 21, 45, 45, 93, 3, 9, 9, 21, 9, 21, 21, 45, 9, 21, 21, 45, 21, 45, 45, 93, 9, 21, 21, 45, 21, 45, 45, 93, 21, 45, 45, 93, 45, 93, 93, 189, 3, 9, 9, 21, 9, 21, 21, 45, 9, 21, 21, 45, 21, 45, 45, 93
Offset: 1

Views

Author

David Applegate and Omar E. Pol, Jan 18 2016

Keywords

Comments

Number of Y-toothpicks added at n-th stage in the structure of A266532.
A simplified version of A160121.

Examples

			Written as an irregular triangle in which the row lengths are the terms of A011782 the sequence begins:
1;
3;
3, 9;
3, 9, 9, 21;
3, 9, 9, 21, 9, 21, 21, 45;
3, 9, 9, 21, 9, 21, 21, 45, 9, 21, 21, 45, 21, 45, 45, 93;
...
Observation: at least the first 11 terms of the right border coincide with A068156.

Links

Crossrefs

Cf. A000120, A011782, A038573, A068156. A139251, A147582, A160121, A151710, A160721, A266532, A267701.

Formula

a(1) = 1. It appears that a(n) = 3*A038573(n-1), n >= 2.
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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