A220959 T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, diagonal and antidiagonal neighbors in a random 0..3 nXk array

1, 1, 1, 2, 6, 1, 4, 19, 23, 1, 7, 76, 142, 94, 1, 12, 267, 1769, 1224, 380, 1, 21, 1074, 15640, 33708, 9500, 1494, 1, 37, 4069, 135445, 627760, 590009, 74689, 5939, 1, 65, 15916, 1135785, 11214779

Offset

1,4

Comments

Table starts

.1....1.....2......4......7.......12......21....37.65

.1....6....19.....76....267.....1074....4069.15916

.1...23...142...1769..15640...135445.1135785

.1...94..1224..33708.627760.11214779

.1..380..9500.590009

.1.1494.74689

.1.5939

.1

Links

Table of n, a(n) for n=1..40.

Example

Some solutions for n=3 k=4
..0..0..0..0....1..0..0..1....0..1..1..1....0..1..1..0....0..1..0..0
..0..0..1..0....1..0..0..0....0..1..0..1....0..0..0..1....0..0..1..0
..1..1..0..0....0..0..1..0....0..0..1..0....0..0..1..1....1..0..1..1

Crossrefs

Column 2 is A220372

Row 1 is A005251(n+1)

Row 2 is A220795

Sequence in context: A220406 A372261 A220794 * A360598 A243434 A265416

Adjacent sequences: A220956 A220957 A220958 * A220960 A220961 A220962

Keyword

nonn,tabl

Author

R. H. Hardin Dec 26 2012

Status

approved