A197042 - OEIS

A197042

Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,2,0,1,3 for x=0,1,2,3,4

2, 20, 120, 698, 4080, 24074, 141856, 833758, 4909544, 28899922, 170120402, 1001361542, 5894102732, 34694985108, 204224876622, 1202124327402, 7076038423114, 41651567268298, 245173129915012, 1443158678807678

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

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

Column 3 of A197047

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +6*a(n-2) +39*a(n-3) +104*a(n-4) +320*a(n-5) -266*a(n-6) +209*a(n-7) -606*a(n-8) +472*a(n-9) -2199*a(n-10) -4220*a(n-11) -79*a(n-12) -4287*a(n-13) -1432*a(n-14) +665*a(n-15) -2303*a(n-16) -1803*a(n-17) +149*a(n-18) +1299*a(n-19) +3913*a(n-20) +1651*a(n-21) -2432*a(n-22) -901*a(n-23) +874*a(n-24) +148*a(n-25) -184*a(n-26) -32*a(n-27)

EXAMPLE

Some solutions for n=4

..1..2..0....1..0..2....0..2..0....0..0..0....0..0..2....1..0..1....2..0..0

..0..0..0....2..0..0....2..2..0....2..1..1....2..1..0....2..0..2....0..2..1

..2..2..1....0..1..2....0..0..2....0..0..2....0..1..0....0..1..0....0..2..1

..0..0..0....2..0..0....2..0..1....1..2..0....0..2..0....0..2..0....2..0..0

CROSSREFS

Sequence in context: A219759 A196797 A196585 * A350549 A062189 A203605

Adjacent sequences: A197039 A197040 A197041 * A197043 A197044 A197045

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 08 2011

STATUS

approved