A252532 T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 3 6 or 7.
750, 730, 595, 621, 337, 460, 719, 341, 334, 535, 778, 462, 466, 426, 546, 932, 706, 626, 610, 676, 649, 1200, 1000, 1120, 790, 1114, 964, 823, 1498, 1468, 1760, 1592, 1676, 1748, 1344, 1036, 1968, 2420, 2404, 2440, 4420, 2504, 2332, 2312, 1328, 2708, 3480
Offset: 1
Examples
Some solutions for n=4 k=4 ..2..2..3..2..2..3....1..1..0..1..1..0....3..2..2..3..2..2....0..2..1..0..1..1 ..3..2..2..3..2..2....2..0..0..3..0..0....3..0..3..3..0..3....0..2..0..0..3..3 ..3..0..3..3..0..3....1..0..1..1..0..1....2..2..3..2..2..3....1..1..0..1..1..0 ..2..2..3..2..2..3....1..1..0..1..1..0....3..2..2..3..2..2....0..1..1..0..1..1 ..3..2..2..3..2..2....3..0..0..2..0..0....3..1..3..3..0..3....0..3..0..0..3..0 ..0..0..3..3..1..3....1..0..1..1..0..1....2..2..3..2..2..3....1..1..0..1..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..612
Formula
Empirical for column k:
k=1: a(n) = 4*a(n-3) -3*a(n-6) -4*a(n-9) +4*a(n-12) for n>23
k=2: a(n) = 6*a(n-3) -8*a(n-6) for n>10
k=3: a(n) = 6*a(n-3) -8*a(n-6) for n>8
k=4: a(n) = 4*a(n-3) for n>5
k=5: a(n) = 12*a(n-3) -32*a(n-6) for n>8
k=6: a(n) = 12*a(n-3) -32*a(n-6) for n>8
k=7: a(n) = 8*a(n-3) for n>5
Empirical for row n:
n=1: a(n) = 4*a(n-3) -3*a(n-6) -4*a(n-9) +4*a(n-12) for n>39
n=2: a(n) = 6*a(n-3) -8*a(n-6) for n>10
n=3: a(n) = 6*a(n-3) -8*a(n-6) for n>8
n=4: a(n) = 4*a(n-3) for n>5
n=5: a(n) = 12*a(n-3) -32*a(n-6) for n>8
n=6: a(n) = 12*a(n-3) -32*a(n-6) for n>8
n=7: a(n) = 8*a(n-3) for n>5
Comments