A197426 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,0,1,1,1 for x=0,1,2,3,4

4, 20, 68, 448, 2152, 10684, 55567, 280544, 1425111, 7280350, 37165198, 189316196, 965915209, 4926863205, 25123365839, 128156345456, 653685106884, 3334114760247, 17006120383127, 86741818975198, 442435364449588

Offset

1,1

Comments

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

Column 3 of A197431

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +8*a(n-2) +2*a(n-3) -55*a(n-4) +13*a(n-5) -31*a(n-6) -1395*a(n-7) -7003*a(n-8) +190*a(n-9) +23621*a(n-10) +39494*a(n-11) +136485*a(n-12) +189052*a(n-13) +97313*a(n-14) -54613*a(n-15) -41550*a(n-16) -8281*a(n-17) -61318*a(n-18) -115671*a(n-19) -54446*a(n-20) +31678*a(n-21) -10581*a(n-22) +13927*a(n-23) -1446*a(n-24) +8349*a(n-25) -8652*a(n-26) +4905*a(n-27) -966*a(n-28) +1251*a(n-29) -457*a(n-30) -57*a(n-31) +6*a(n-32) +a(n-34)

Example

Some solutions for n=4
..1..1..1....1..1..0....1..1..2....0..1..2....1..2..0....1..1..0....1..0..0
..0..0..0....0..1..1....0..0..1....0..1..1....0..1..2....0..2..1....2..2..1
..0..0..0....1..1..2....1..1..2....1..2..0....1..1..1....1..3..1....1..1..2
..1..2..1....1..0..0....2..1..0....1..0..0....1..0..0....2..1..0....0..0..0

Crossrefs

Sequence in context: A006740 A291526 A303011 * A061981 A054611 A329174

Adjacent sequences: A197423 A197424 A197425 * A197427 A197428 A197429

Keyword

nonn

Author

R. H. Hardin Oct 14 2011

Status

approved