A252410 Number of (3+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 2 3 4 6 or 7

319, 688, 1515, 2555, 7425, 18377, 32710, 97923, 245711, 440341, 1327285, 3343809, 6005069, 18174197, 45900357, 82546379, 250597823, 634117095, 1141608889, 3474085061, 8803935237, 15862997397, 48363153977, 122700674105, 221224063343

Offset

1,1

Comments

Row 3 of A252407

Links

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

Formula

Empirical: a(n) = 26*a(n-3) -179*a(n-6) +122*a(n-9) +562*a(n-12) -680*a(n-15) -425*a(n-18) +768*a(n-21) +19*a(n-24) -236*a(n-27) +24*a(n-30) for n>37

Example

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

Crossrefs

Sequence in context: A153048 A053020 A250660 * A064905 A293921 A121010

Adjacent sequences: A252407 A252408 A252409 * A252411 A252412 A252413

Keyword

nonn

Author

R. H. Hardin, Dec 17 2014

Status

approved