A252386 - OEIS

A252386

Number of (2+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 3 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 3 5 6 or 7

540, 555, 647, 771, 1067, 1496, 1928, 2662, 3856, 5074, 7024, 10213, 13505, 18776, 27325, 36221, 50467, 73399, 97476, 135968, 197447, 262661, 366593, 531297, 707931, 988319, 1429275, 1907450, 2663225, 3843093, 5136589, 7172051, 10327393

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Row 2 of A252384

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-3) -32*a(n-6) +58*a(n-9) -58*a(n-12) +32*a(n-15) -9*a(n-18) +a(n-21) for n>30

EXAMPLE

Some solutions for n=4

..1..0..2..1..0..2....0..2..3..0..3..3....2..0..3..0..0..3....3..2..1..3..2..1

..0..0..0..0..0..0....1..3..1..1..3..1....1..0..2..1..0..2....2..0..3..0..0..3

..0..1..2..0..1..2....3..3..0..3..3..0....1..2..3..1..2..3....3..2..0..1..2..0

..1..0..2..1..3..2....0..3..3..0..2..1....0..0..3..0..0..3....3..2..1..3..2..1

CROSSREFS

Sequence in context: A239347 A118630 A184546 * A289221 A345390 A261290

Adjacent sequences: A252383 A252384 A252385 * A252387 A252388 A252389

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 17 2014

STATUS

approved