A252070 Number of (n+2)X(3+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 or 4.

183, 419, 1497, 5085, 17455, 60245, 206747, 711749, 2455039, 8451165, 29078125, 100127009, 344830169, 1187280673, 4087598979, 14073866379, 48459148697, 166851565147, 574482172193, 1977991833479, 6810453196661, 23449166058617

Offset: 1

Author

R. H. Hardin, Dec 13 2014

Keywords

• nonn

Comments

Column 3 of A252075

Examples

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

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +11*a(n-3) +20*a(n-4) +12*a(n-5) -7*a(n-6) -69*a(n-7) -49*a(n-8) +69*a(n-9) +59*a(n-10) -9*a(n-11) -30*a(n-12) -14*a(n-13) +2*a(n-14) +4*a(n-16) for n>18