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.

A167251 Number of ways to partition an n X 5 grid into 5 connected equal-area regions.

Original entry on oeis.org

1, 8, 62, 454, 4006, 33344, 270827, 2152050, 15661597, 113764225, 757566033
Offset: 1

Views

Author

R. H. Hardin Oct 31 2009

Keywords

Examples

			Some solutions for n=3
...1.1.2.2.2...1.1.1.2.3...1.2.3.4.4...1.1.2.2.3...1.1.1.2.3...1.2.2.2.3
...3.1.4.5.5...4.5.5.2.3...1.2.3.5.4...1.4.2.3.3...4.4.5.2.3...1.4.4.4.3
...3.3.4.4.5...4.4.5.2.3...1.2.3.5.5...4.4.5.5.5...4.5.5.2.3...1.5.5.5.3
------
...1.1.2.2.2...1.1.1.2.2...1.1.2.2.3...1.2.2.3.3...1.1.2.3.3...1.2.3.3.4
...1.3.4.4.4...3.4.4.5.2...4.1.2.3.3...1.1.2.3.4...4.1.2.3.5...1.2.3.5.4
...3.3.5.5.5...3.3.4.5.5...4.4.5.5.5...5.5.5.4.4...4.4.2.5.5...1.2.5.5.4
------
...1.2.2.3.3...1.2.3.4.5...1.2.2.2.3...1.2.2.3.3...1.2.3.3.3...1.2.2.3.4
...1.2.4.5.3...1.2.3.4.5...1.1.4.4.3...1.2.4.3.5...1.2.4.4.5...1.2.3.3.4
...1.4.4.5.5...1.2.3.4.5...5.5.5.4.3...1.4.4.5.5...1.2.4.5.5...1.5.5.5.4
------
...1.1.2.3.3...1.1.2.2.2...1.1.2.3.4...1.1.2.2.3...1.1.2.2.2...1.1.2.3.3
...1.2.2.4.3...1.3.4.5.5...1.5.2.3.4...4.1.2.5.3...3.1.4.4.4...1.4.2.2.3
...5.5.5.4.4...3.3.4.4.5...5.5.2.3.4...4.4.5.5.3...3.3.5.5.5...4.4.5.5.5
		

Formula

a(n) = A167261(n,5). - R. J. Mathar, Oct 13 2024