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.

A055397 Maximum population of an n X n stable pattern in Conway's Game of Life.

Original entry on oeis.org

0, 4, 6, 8, 16, 18, 28, 36, 43, 54, 64, 76, 90, 104, 119, 136, 152, 171, 190, 210, 232, 253, 276, 301, 326, 352, 379, 407, 437, 467, 497, 531, 563, 598, 633, 668, 706, 744, 782, 824, 864, 907, 949, 993, 1039, 1085, 1132, 1181, 1229, 1280, 1331, 1382, 1436
Offset: 1

Views

Author

Stephen A. Silver, Jun 25 2000

Keywords

Examples

			a(3) = 6 because a ship has 6 cells and no other 3 X 3 stable pattern has more.
		

Formula

a(n) = (n^2)/2 + O(n).
For n >= 55, floor(n^2/2 + 17*n/27 - 2) <= a(n) <= ceiling(n^2/2 + 17*n/27 - 2), which gives all values of this sequence within +- 1.

Extensions

a(11)-a(27) from Nathaniel Johnston, May 15 2011, based on table in Chu et al.
a(28)-a(53) from Nathaniel Johnston, Nov 27 2013, based on work by Chu et al.