A163707 Number of n X 5 binary arrays with all 1s connected, a path of 1s from left column to lower right corner, and no 1 having more than two 1s adjacent.

1, 18, 138, 775, 3643, 15350, 62079, 245117, 941073, 3502398, 12690043, 45061490, 157594709, 544310928, 1859600880, 6292850267, 21119509648, 70373235569, 233024362713, 767309824020, 2514027582768, 8200071794701, 26638061694756, 86216040356410, 278109117426636

Offset

1,2

Links

Andrew Howroyd, Table of n, a(n) for n = 1..500

Example

All solutions for n=2:
...0.0.0.0.0...0.0.0.0.1...1.0.0.0.0...1.0.0.0.1...1.1.0.0.0...1.1.0.0.1
...1.1.1.1.1...1.1.1.1.1...1.1.1.1.1...1.1.1.1.1...0.1.1.1.1...0.1.1.1.1
------
...1.1.1.0.0...1.1.1.0.1...1.1.1.0.0...1.1.1.0.1...1.1.1.1.0...1.1.1.1.0
...0.0.1.1.1...0.0.1.1.1...1.0.1.1.1...1.0.1.1.1...0.0.0.1.1...1.0.0.1.1
------
...1.1.1.1.1...1.1.1.1.1...0.0.1.1.1...1.0.1.1.1...0.1.1.1.0...0.1.1.1.1
...0.0.0.0.1...1.0.0.0.1...1.1.1.0.1...1.1.1.0.1...1.1.0.1.1...1.1.0.0.1

Crossrefs

Row 5 of A391823.

Sequence in context: A239208 A114239 A087115 * A212154 A108680 A204273

Adjacent sequences: A163704 A163705 A163706 * A163708 A163709 A163710

Keyword

nonn

Author

R. H. Hardin, Aug 03 2009

Extensions

a(15) onward from Andrew Howroyd, Dec 23 2025

Status

approved