A221288 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give

A221288

Equals two maps: number of nX5 binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..3 nX5 array

7, 200, 5912, 172904, 4983598, 143511784, 4129628435, 118813480496, 3418203388701, 98338490101681, 2829094038032543, 81389941488977962, 2341498869979723606, 67362334665049967042, 1937939871911867309221

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 5 of A221290

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Some solutions for n=3

..0..1..1..0..1....0..0..0..0..0....0..0..0..0..0....0..0..0..1..0

..1..0..0..1..1....0..0..0..0..0....0..0..0..0..1....1..1..1..1..1

..0..0..0..1..0....1..0..1..0..0....1..1..1..1..0....0..0..1..0..0