A252365 Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 3 4 6 or 7

658, 2338, 10450, 45516, 192946, 818040, 3482672, 14848406, 63260032, 269276490, 1146479186, 4882764600, 20793914762, 88545635100, 377056380768, 1605668962346, 6837603120792, 29117161531894, 123992231041454

Offset

1,1

Comments

Column 4 of A252369

Links

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

Formula

Empirical: a(n) = a(n-1) +6*a(n-2) +20*a(n-3) +54*a(n-4) +38*a(n-5) -41*a(n-6) -191*a(n-7) -285*a(n-8) +296*a(n-9) +753*a(n-10) -160*a(n-11) -791*a(n-12) -99*a(n-13) +334*a(n-14) +98*a(n-15) -18*a(n-16) +54*a(n-17) -3*a(n-18) -35*a(n-19) +3*a(n-20) -12*a(n-21) -7*a(n-22) +4*a(n-23) for n>25

Example

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

Crossrefs

Sequence in context: A034818 A210091 A068260 * A198207 A171393 A349586

Adjacent sequences: A252362 A252363 A252364 * A252366 A252367 A252368

Keyword

nonn

Author

R. H. Hardin, Dec 17 2014

Status

approved