A253694 Number of (n+1)X(4+1) 0..1 arrays with every 2X2 subblock ne-sw antidiagonal difference unequal to its neighbors horizontally and nw+se diagonal sum unequal to its neighbors vertically

264, 282, 356, 700, 1120, 1638, 3136, 4782, 7926, 14462, 22656, 39334, 68068, 110254, 193022, 326064, 542916, 941302, 1578364, 2668696, 4579938, 7691528, 13087264, 22287082, 37577096, 64014484, 108601422, 183741636, 312684956, 529783652

Offset

1,1

Comments

Column 4 of A253698

Links

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

Formula

Empirical: a(n) = 3*a(n-2) +2*a(n-3) -a(n-4) -a(n-6) -13*a(n-7) -8*a(n-8) +9*a(n-9) +a(n-10) +13*a(n-11) +31*a(n-12) -11*a(n-13) -26*a(n-14) +7*a(n-15) -5*a(n-16) -15*a(n-17) +7*a(n-18) +6*a(n-19) -2*a(n-20) +2*a(n-21) +2*a(n-22) for n>24

Example

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

Crossrefs

Sequence in context: A065570 A345586 A345844 * A253701 A255804 A351802

Adjacent sequences: A253691 A253692 A253693 * A253695 A253696 A253697

Keyword

nonn

Author

R. H. Hardin, Jan 09 2015

Status

approved