A222871 T(n,k)=Number of nXk 0..5 arrays with no element equal to another at a city block distance of exactly two, and new values 0..5 introduced in row major order

1, 2, 2, 3, 7, 3, 7, 34, 34, 7, 20, 370, 816, 370, 20, 67, 5314, 30528, 30528, 5314, 67, 254, 82690, 1186704, 2903520, 1186704, 82690, 254, 1057, 1313794, 46269792, 276768768, 276768768, 46269792, 1313794, 1057, 4700, 20983810, 1804486896, 26393020608

Offset

1,2

Comments

Table starts

.....1.........2...........3.............7.............20.............67

.....2.........7..........34...........370...........5314..........82690

.....3........34.........816.........30528........1186704.......46269792

.....7.......370.......30528.......2903520......276768768....26393020608

....20......5314.....1186704.....276768768....64508270616.15035444690880

....67.....82690....46269792...26393020608.15035444690880

...254...1313794..1804486896.2516653274112

..1057..20983810.70374883968

..4700.335593474

.21847

Links

R. H. Hardin, Table of n, a(n) for n = 1..59

Formula

Empirical for column k:

k=1: a(n) = 11*a(n-1) -41*a(n-2) +61*a(n-3) -30*a(n-4) for n>6

k=2: a(n) = 21*a(n-1) -84*a(n-2) +64*a(n-3) for n>5

k=3: a(n) = 42*a(n-1) -117*a(n-2) for n>4

Example

Some solutions for n=3 k=4
..0..1..2..0....0..1..2..3....0..1..2..3....0..1..2..3....0..1..1..2
..0..3..4..0....0..1..4..4....4..1..5..4....4..5..0..4....3..3..0..4
..4..2..5..3....2..3..0..1....3..3..5..1....2..2..3..4....2..4..5..1

Crossrefs

Sequence in context: A183407 A222838 A222944 * A222779 A222894 A210753

Adjacent sequences: A222868 A222869 A222870 * A222872 A222873 A222874

Keyword

nonn,tabl

Author

R. H. Hardin Mar 07 2013

Status

approved