A208430 Number of nX4 0..2 arrays with new values 0..2 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors)

14, 216, 339, 1292, 6416, 32813, 169899, 885540, 4617014, 24074947, 125562891, 654899967, 3415879346, 17817085346, 92933586111, 484741782266, 2528419901343, 13188283797088, 68790359883448, 358812044639010, 1871571851010931

Offset

1,1

Comments

Column 4 of A208434

Links

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

Formula

Empirical: a(n) = 7*a(n-1) -6*a(n-2) -11*a(n-3) -36*a(n-4) -39*a(n-5) +276*a(n-6) +153*a(n-7) -71*a(n-8) -518*a(n-9) -1682*a(n-10) +1463*a(n-11) +2788*a(n-12) -2181*a(n-13) -273*a(n-14) +1238*a(n-15) -2067*a(n-16) +301*a(n-17) +1071*a(n-18) -635*a(n-19) +133*a(n-20) +286*a(n-21) -194*a(n-22) -38*a(n-23) +80*a(n-24) -46*a(n-25) -14*a(n-26) +20*a(n-27) -4*a(n-28) for n>34

Example

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

Crossrefs

Sequence in context: A240326 A202976 A331494 * A275224 A275144 A275354

Adjacent sequences: A208427 A208428 A208429 * A208431 A208432 A208433

Keyword

nonn

Author

R. H. Hardin Feb 26 2012

Status

approved