A165387 Number of slanted 4Xn (i=1..4)X(j=i..n+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, and 4 in the lower right corner

5, 104, 1409, 11960, 85841, 534816, 3017385, 15787165, 77891237, 366749318, 1662432947, 7302379696, 31240817911, 130688934607, 536275945765, 2164142120076, 8606910817129, 33793586661904, 131185521194097

Offset

2,1

Links

R. H. Hardin, Table of n, a(n) for n=2..22

Example

Some solutions for n=4
...1.1.2.2.........1.1.4.2.........1.1.2.2.........1.1.2.2......
.....1.3.2.2.........4.4.4.4.........1.3.3.3.........1.2.2.2....
.......3.3.2.2.........4.3.4.4.........3.3.3.3.........3.3.2.2..
.........3.3.3.4.........3.3.4.4.........3.3.4.4.........3.2.2.4
------
...1.1.2.2.........1.1.1.2.........1.2.2.2.........1.1.2.2......
.....1.1.2.2.........1.2.2.2.........2.2.2.2.........1.1.2.1....
.......1.1.2.4.........3.3.4.4.........3.3.4.4.........1.1.1.1..
.........3.4.4.4.........3.3.4.4.........3.4.4.4.........3.3.4.4
------
...1.1.1.2.........1.1.1.2.........1.1.2.2.........1.1.2.2......
.....1.1.3.3.........2.2.2.2.........2.2.4.4.........3.3.2.2....
.......1.3.4.4.........2.2.2.4.........2.2.4.4.........3.3.2.2..
.........3.3.4.4.........3.4.4.4.........3.4.4.4.........3.3.4.4

Crossrefs

Sequence in context: A163212 A163154 A354157 * A361138 A156848 A057016

Adjacent sequences: A165384 A165385 A165386 * A165388 A165389 A165390

Keyword

nonn

Author

R. H. Hardin Sep 17 2009

Status

approved