A240645 Number of nX4 0..1 arrays with no element equal to the same number of vertical neighbors as horizontal neighbors, with new values 0..1 introduced in row major order

2, 3, 8, 18, 61, 168, 526, 1643, 5524, 18762, 65149, 228440, 807770, 2872483, 10255424, 36709394, 131630309, 472542776, 1697728566, 6102699043, 21944561100, 78928279002, 283926402165, 1021465508456, 3675119389202, 13223276351667

Offset

1,1

Comments

Column 4 of A240649

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -5*a(n-2) +4*a(n-3) -3*a(n-4) -49*a(n-5) +10*a(n-6) +15*a(n-7) +45*a(n-8) +124*a(n-9) +131*a(n-10) +301*a(n-11) +18*a(n-12) -615*a(n-13) -201*a(n-14) -1508*a(n-15) -823*a(n-16) -413*a(n-17) -254*a(n-18) +2467*a(n-19) +793*a(n-20) +4516*a(n-21) +1071*a(n-22) +2289*a(n-23) -2289*a(n-25) -1071*a(n-26) -4516*a(n-27) -793*a(n-28) -2467*a(n-29) +254*a(n-30) +413*a(n-31) +823*a(n-32) +1508*a(n-33) +201*a(n-34) +615*a(n-35) -18*a(n-36) -301*a(n-37) -131*a(n-38) -124*a(n-39) -45*a(n-40) -15*a(n-41) -10*a(n-42) +49*a(n-43) +3*a(n-44) -4*a(n-45) +5*a(n-46) -5*a(n-47) +a(n-48)

Example

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

Crossrefs

Sequence in context: A317722 A113183 A157015 * A273754 A242099 A041205

Adjacent sequences: A240642 A240643 A240644 * A240646 A240647 A240648

Keyword

nonn

Author

R. H. Hardin, Apr 09 2014

Status

approved