A165390 Number of slanted 7Xn (i=1..7)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

11, 296, 24225, 993780, 33107075, 948440084, 25614600093, 655460808868

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............
.....1.1.2.2.3.3.2.2..........
.......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..
...............3.4.4.4.4.4.4.4

Crossrefs

Sequence in context: A133515 A258191 A350938 * A213256 A067424 A001538

Adjacent sequences: A165387 A165388 A165389 * A165391 A165392 A165393

Keyword

nonn

Author

R. H. Hardin Sep 17 2009

Status

approved