A232253 Number of (n+1)X(4+1) 0..2 arrays with every element both >= and <= some horizontal or antidiagonal neighbor

1287, 96999, 7258599, 544777651, 40896843985, 3070212041183, 230487644229167, 17303223331864431, 1298991725349537089, 97518218023627044295, 7320911028394527687575, 549597186787143997790315

Offset

1,1

Comments

Column 4 of A232257

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 69*a(n-1) +555*a(n-2) -7271*a(n-3) -16398*a(n-4) +266152*a(n-5) -265357*a(n-6) -2539887*a(n-7) -7724280*a(n-8) -6811008*a(n-9) +16331136*a(n-10) +18397456*a(n-11) -13469384*a(n-12) -10822060*a(n-13) +6278955*a(n-14) +1333583*a(n-15) -1195787*a(n-16) +285229*a(n-17) -45161*a(n-18) +3471*a(n-19) -6*a(n-20) -6*a(n-21)

Example

Some solutions for n=2
..1..1..0..2..2....2..2..1..0..0....0..0..0..0..1....2..2..1..1..2
..1..0..1..2..1....1..0..2..2..2....2..2..2..2..2....2..2..1..2..2
..2..2..2..1..1....0..0..1..1..1....2..2..2..0..0....2..0..0..0..0

Crossrefs

Sequence in context: A084803 A104399 A353347 * A140914 A239436 A239939

Adjacent sequences: A232250 A232251 A232252 * A232254 A232255 A232256

Keyword

nonn

Author

R. H. Hardin, Nov 21 2013

Status

approved