A252215 Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 5 6 or 7

3147, 2836, 10486, 44776, 188866, 801122, 3410786, 14539238, 61939226, 263654432, 1122558798, 4780929468, 20360099382, 86698049968, 369189620578, 1572170465502, 6694947958402, 28509673198294, 121405330624876

Offset

1,1

Comments

Column 4 of A252219

Links

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

Formula

Empirical: a(n) = a(n-1) +6*a(n-2) +21*a(n-3) +53*a(n-4) +32*a(n-5) -61*a(n-6) -245*a(n-7) -323*a(n-8) +337*a(n-9) +944*a(n-10) +125*a(n-11) -1087*a(n-12) -852*a(n-13) +494*a(n-14) +889*a(n-15) +81*a(n-16) -280*a(n-17) -101*a(n-18) -17*a(n-19) -51*a(n-20) -9*a(n-21) +28*a(n-22) +a(n-23) +12*a(n-24) +7*a(n-25) -4*a(n-26) for n>29

Example

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

Crossrefs

Sequence in context: A172961 A172720 A276686 * A250760 A184452 A151750

Adjacent sequences: A252212 A252213 A252214 * A252216 A252217 A252218

Keyword

nonn

Author

R. H. Hardin, Dec 15 2014

Status

approved