A196644 Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 1,3,4,0,2 for x=0,1,2,3,4

1, 41, 356, 2783, 25118, 217880, 1921822, 16668173, 146029787, 1275692776, 11144916533, 97386223456, 850945201900, 7435399467018, 64968547774607, 567683242015249, 4960297439355274, 43342029653468635, 378713657086113296

Offset

1,2

Comments

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

Column 6 of A196646

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +30*a(n-2) +96*a(n-3) +108*a(n-4) -488*a(n-5) -1920*a(n-6) +2726*a(n-7) +2921*a(n-8) -12404*a(n-9) +18929*a(n-10) -14229*a(n-11) -19708*a(n-12) +81563*a(n-13) -68602*a(n-14) -24662*a(n-15) +140418*a(n-16) -182142*a(n-17) +110085*a(n-18) -806*a(n-19) -64045*a(n-20) +51183*a(n-21) +4093*a(n-22) -21043*a(n-23) +315*a(n-24) +2438*a(n-25) +544*a(n-26) +385*a(n-27) -331*a(n-28) -78*a(n-29) +82*a(n-30) +26*a(n-31) -2*a(n-32) -a(n-33)

Example

Some solutions for n=4
..0..3..0..0..0..0....0..0..0..0..0..0....0..3..0..3..0..0....0..0..3..0..3..0
..3..0..3..3..0..0....0..0..0..3..0..0....0..0..3..0..0..3....0..0..0..3..0..3
..0..0..0..0..0..0....3..0..0..3..0..3....3..0..3..0..0..0....0..0..0..3..0..0
..0..3..0..0..3..0....0..0..0..0..3..0....0..3..0..0..0..0....0..0..3..0..3..0

Crossrefs

Sequence in context: A300645 A268779 A142501 * A196599 A142571 A270884

Adjacent sequences: A196641 A196642 A196643 * A196645 A196646 A196647

Keyword

nonn

Author

R. H. Hardin Oct 04 2011

Status

approved