A252203 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 1 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 1 3 4 6 or 7

2680, 4743, 9312, 19794, 51024, 125554, 278710, 763726, 1944090, 4393122, 12184346, 31155178, 70732458, 196510762, 502312306, 1143167546, 3175587782, 8108392378, 18490987722, 51342152722, 130937041938, 299194452074

Offset

1,1

Comments

Column 1 of A252210

Links

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

Formula

Empirical: a(n) = a(n-1) +a(n-2) +33*a(n-3) -31*a(n-4) -35*a(n-5) -288*a(n-6) +218*a(n-7) +385*a(n-8) +255*a(n-9) +417*a(n-10) -1371*a(n-11) -54*a(n-12) -992*a(n-13) +1178*a(n-14) +1150*a(n-15) -740*a(n-16) +320*a(n-17) -476*a(n-18) -448*a(n-19) +512*a(n-20) -64*a(n-21) for n>26

Example

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

Crossrefs

Sequence in context: A258512 A254992 A252210 * A252202 A236594 A217335

Adjacent sequences: A252200 A252201 A252202 * A252204 A252205 A252206

Keyword

nonn

Author

R. H. Hardin, Dec 15 2014

Status

approved