A196325 Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 1,3,0,4,2 for x=0,1,2,3,4

3, 23, 68, 295, 1029, 3932, 15029, 56415, 213788, 807845, 3054887, 11551608, 43672327, 165135129, 624374584, 2360781157, 8926215203, 33750290592, 127611145241, 482502180893, 1824357955536, 6897962766699, 26081442528097

Offset

1,1

Comments

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

Column 4 of A196329

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) +9*a(n-3) +12*a(n-4) +24*a(n-5) +6*a(n-6) +33*a(n-7) +4*a(n-8) -28*a(n-9) -6*a(n-10) -38*a(n-11) -17*a(n-12) +3*a(n-13) -17*a(n-14) +2*a(n-15) +2*a(n-16) -2*a(n-17) +2*a(n-18) +2*a(n-19) +2*a(n-20) +a(n-21) +2*a(n-22)

Example

Some solutions for n=5
..0..0..2..0....0..0..0..0....0..0..0..0....0..0..0..2....2..0..0..0
..2..2..2..0....0..2..2..2....0..0..0..0....0..0..0..0....0..0..2..2
..0..0..0..0....0..2..0..0....2..2..2..2....0..2..2..2....2..2..2..0
..0..0..2..2....0..2..2..2....0..0..0..0....0..2..0..0....0..0..0..0
..2..0..2..0....2..0..0..0....2..0..0..2....0..2..0..0....0..2..2..0

Crossrefs

Sequence in context: A300112 A183332 A358422 * A003531 A121984 A107177

Adjacent sequences: A196322 A196323 A196324 * A196326 A196327 A196328

Keyword

nonn

Author

R. H. Hardin Oct 01 2011

Status

approved