A232589 T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or antidiagonally, with no adjacent elements equal.
0, 10, 2, 2, 34, 4, 26, 12, 124, 6, 20, 152, 42, 456, 10, 70, 108, 996, 122, 1686, 18, 90, 690, 606, 6406, 332, 6232, 32, 210, 744, 8104, 3002, 41328, 882, 23034, 56, 336, 3232, 7568, 93236, 14398, 266490, 2322, 85130, 98, 674, 4516, 66744, 68072, 1079300
Offset: 1
Examples
Some solutions for n=5 k=4 ..2..1..2..1..0....2..1..2..1..0....2..1..0..1..2....0..1..2..1..0 ..0..1..2..1..0....0..1..0..1..2....2..1..0..1..2....2..1..0..1..2 ..2..1..2..1..2....0..1..2..1..2....0..1..2..1..0....0..1..2..1..2 ..0..1..2..1..0....0..1..0..1..2....2..1..0..1..2....0..1..0..1..0 ..2..1..2..1..2....0..1..0..1..0....0..1..0..1..0....0..1..2..1..2 ..0..1..0..1..0....2..1..2..1..2....2..1..2..1..0....2..1..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..477
Formula
Empirical for column k:
k=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3)
k=2: a(n) = 4*a(n-1) -a(n-2) -a(n-3) +2*a(n-4)
k=3: a(n) = 4*a(n-1) -4*a(n-2) +a(n-3)
k=4: a(n) = 5*a(n-1) +9*a(n-2) +2*a(n-3) +a(n-4) +2*a(n-5)
k=5: [order 14]
k=6: [order 23] for n>27
k=7: [order 44] for n>45
Empirical for row n:
n=1: a(n) = -a(n-1) +2*a(n-2) +4*a(n-3) +3*a(n-4) +a(n-5)
n=2: [order 9] for n>10
n=3: [order 24] for n>26
n=4: [order 49] for n>54
Comments