A252009 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum 1 3 6 or 8 and every diagonal and antidiagonal sum not 1 3 6 or 8

1168, 1602, 1406, 2002, 3128, 4570, 6562, 10980, 18568, 26866, 47386, 84660, 122946, 224610, 409428, 595934, 1099500, 2017128, 2940062, 5447180, 10020972, 14609852, 27109394, 49938584, 72814596, 135212590, 249247170, 363421408, 675111432

Offset

1,1

Comments

Column 2 of A252015

Links

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

Formula

Empirical: a(n) = 9*a(n-3) +a(n-5) -22*a(n-6) -9*a(n-8) +6*a(n-9) +23*a(n-11) +23*a(n-12) -15*a(n-14) -15*a(n-15) for n>22

Example

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

Crossrefs

Sequence in context: A244428 A221350 A227485 * A032744 A185477 A185469

Adjacent sequences: A252006 A252007 A252008 * A252010 A252011 A252012

Keyword

nonn

Author

R. H. Hardin, Dec 12 2014

Status

approved