A165384 Number of slanted nX7 (i=1..n)X(j=i..7+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, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value

481, 18912, 196082, 1357468, 7051772, 30346872, 113675050, 385459632, 1210822319, 3585582454, 10137294012

Offset

2,1

Links

Table of n, a(n) for n=2..12.

Example

One solution for n=6
...1.1.2.2.2.2.2..........
.....1.1.2.3.2.2.2........
.......1.3.3.2.3.2.2......
.........3.3.2.3.3.4.4....
...........3.3.3.3.3.4.4..
.............3.4.4.4.4.4.4

Crossrefs

Sequence in context: A290338 A365657 A254896 * A365688 A165376 A214170

Adjacent sequences: A165381 A165382 A165383 * A165385 A165386 A165387

Keyword

nonn

Author

R. H. Hardin Sep 17 2009

Status

approved