A197176 Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,2,1,0,0 for x=0,1,2,3,4

3, 23, 150, 969, 7172, 50864, 367813, 2646379, 19073997, 137434440, 990411767, 7137038938, 51431455178, 370627617651, 2670838531897, 19246742767269, 138696965305604, 999485868248461, 7202551374117304, 51903431296093738

Offset

1,1

Comments

Every 0 is next to 0 2's, every 1 is next to 1 2's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's

Column 4 of A197180

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +14*a(n-2) +13*a(n-3) +51*a(n-4) -242*a(n-5) -605*a(n-6) -267*a(n-7) -603*a(n-8) +944*a(n-9) +6252*a(n-10) +4235*a(n-11) -16376*a(n-12) +13174*a(n-13) -2828*a(n-14) -4321*a(n-15) +13660*a(n-16) -66695*a(n-17) +105055*a(n-18) -21147*a(n-19) -55248*a(n-20) -32618*a(n-21) -36869*a(n-22) +32581*a(n-23) +112818*a(n-24) +91398*a(n-25) -191452*a(n-26) +22561*a(n-27) +9994*a(n-28) +74786*a(n-29) +25052*a(n-30) -106048*a(n-31) +43131*a(n-32) -47104*a(n-33) +18400*a(n-34) +18484*a(n-35) -37276*a(n-36) +21617*a(n-37) +10180*a(n-38) +3318*a(n-39) +287*a(n-40) -9682*a(n-41) +1636*a(n-42) +1408*a(n-43) -284*a(n-44) -8*a(n-45) -16*a(n-46)

Example

Some solutions containing all values 0 to 4 for n=5
..0..0..0..0....0..3..0..0....0..3..0..0....0..0..3..0....0..1..2..1
..0..4..0..0....0..0..0..0....1..0..4..0....0..4..0..0....0..0..3..0
..3..0..4..0....0..4..0..0....2..1..0..0....0..0..4..0....0..4..0..3
..0..0..0..1....3..0..3..0....2..1..3..0....0..3..0..3....1..0..4..0
..0..0..1..2....0..1..2..1....1..0..0..0....1..2..1..0....2..1..0..0

Crossrefs

Sequence in context: A057835 A232145 A079755 * A264461 A006184 A308677

Adjacent sequences: A197173 A197174 A197175 * A197177 A197178 A197179

Keyword

nonn

Author

R. H. Hardin Oct 11 2011

Status

approved