A165377 Number of slanted nX8 (i=1..n)X(j=i..8+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.

869, 82224, 3017385, 74493401, 1484483677, 25614600093, 397609974217, 5695358682045

Offset

2,1

Links

Table of n, a(n) for n=2..9.

Example

One solution for n=8
...1.1.2.2.2.2.2.2..............
.....1.1.2.2.2.2.2.2............
.......1.1.2.2.3.3.2.2..........
.........1.2.3.3.3.3.2.2........
...........3.3.3.3.3.3.3.4......
.............3.3.3.3.3.4.4.4....
...............3.3.3.4.4.4.4.4..
.................3.3.3.3.3.3.4.4

Crossrefs

Sequence in context: A251060 A205224 A165385 * A283449 A351878 A158669

Adjacent sequences: A165374 A165375 A165376 * A165378 A165379 A165380

Keyword

nonn

Author

R. H. Hardin, Sep 17 2009

Status

approved