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.

Showing 1-3 of 3 results.

A151837 a(n) = A151836(n)/4.

Original entry on oeis.org

1, 1, 3, 1, 3, 3, 7, 1, 3, 3, 7, 5, 7, 9, 17, 1, 3, 3, 7, 5, 7, 9, 17, 9, 7, 9, 17, 17, 19, 25, 43, 3, 7, 3, 7, 5, 7, 9, 17, 9, 7, 9, 17, 17, 19, 25, 43, 19, 7, 9, 17, 17, 19, 25, 43, 35, 23, 25, 43, 51, 55, 69, 113, 15, 23, 3, 7, 5, 7, 9, 17, 9, 7, 9, 17, 17
Offset: 2

Views

Author

N. J. A. Sloane, Jul 13 2009

Keywords

Crossrefs

Cf. A151836.

Extensions

More terms from Rémy Sigrist, Jan 08 2022

A151776 Number of ON states after n generations of cellular automaton based on f.c.c. lattice with each cell adjacent to its twelve neighbors.

Original entry on oeis.org

0, 1, 13, 25, 109, 121, 205, 385, 805, 817, 901, 1081, 1645, 2185, 2605, 3721, 5749, 5857, 5941, 6121, 6685, 7225, 7789, 9289, 12565, 14401, 14821, 15937, 18877, 23257, 25981, 32233, 42445, 43729, 44101, 44521
Offset: 0

Views

Author

N. J. A. Sloane, Jun 24 2009

Keywords

Comments

We take the f.c.c. lattice to consist of the points (X,Y,Z) of Z^3 with X+Y+Z even.
We start with a single ON cell at the origin.
A cell is turned ON if exactly one of its twelve neighbors is ON. An ON cell remains ON forever.
Analog of A147562, which is corresponding sequence for the square lattice Z^2.
If we just look at what happens in the (X,Y)-plane, we get A147552 and A151836.

Crossrefs

Extensions

Terms after a(30) from Nathaniel Johnston, Mar 27 2011

A147552 Consider the cellular automaton based on the f.c.c. lattice described in A151776; sequence gives number of ON cells in generation n that lie in the (x,y) plane.

Original entry on oeis.org

0, 1, 5, 9, 21, 25, 37, 49, 77, 81, 93, 105, 133, 153, 181, 217, 285, 289, 301, 313, 341, 361, 389, 425, 493, 529, 557, 593, 661, 729, 805, 905, 1077, 1089, 1117, 1129, 1157, 1177, 1205, 1241, 1309, 1345, 1373, 1409, 1477, 1545, 1621, 1721, 1893, 1969, 1997, 2033
Offset: 0

Views

Author

N. J. A. Sloane, Jul 13 2009

Keywords

Comments

First differs from A160720 at a(13).

Crossrefs

Cf. A151776, A151836 (first differences), A139250.

Extensions

Terms after a(30) from Nathaniel Johnston, Mar 27 2011
Showing 1-3 of 3 results.