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A252960
Number of (n+2) X (7+2) 0..4 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order.
1
7495, 1069, 1429, 2349, 4019, 6855, 12573, 23471, 42337, 81323, 155799, 290009, 563689, 1097993, 2074061, 4075537, 7986375, 15324923, 30226561, 59683643, 115596469, 229227527, 454031043, 887656421, 1763720581, 3506651437
OFFSET
1,1
COMMENTS
Column 7 of A252961.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +a(n-2) +3*a(n-3) -30*a(n-4) -12*a(n-5) +67*a(n-6) +51*a(n-7) +41*a(n-8) -341*a(n-9) +162*a(n-10) -28*a(n-11) +261*a(n-12) -195*a(n-13) -9*a(n-14) +73*a(n-15) -30*a(n-16) +8*a(n-17) -71*a(n-18) +45*a(n-19) -a(n-20) +9*a(n-21) -6*a(n-22) for n>25.
EXAMPLE
Some solutions for n=2
..0..0..1..0..0..2..0..0..1....0..1..1..2..1..1..2..1..1
..1..3..3..0..3..3..0..3..3....1..0..1..1..2..1..1..0..0
..4..4..0..0..1..0..0..2..0....3..3..1..3..3..1..3..3..2
..0..0..1..0..0..1..0..0..2....2..1..1..0..1..1..2..1..1
CROSSREFS
Cf. A252961.
Sequence in context: A250239 A330713 A253338 * A258612 A258605 A258604
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 25 2014
STATUS
approved