A251823 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum not 3 or 6 and every diagonal and antidiagonal sum 3 or 6

3930, 8674, 28202, 75498, 284506, 1095314, 3073138, 12215010, 49634706, 140568394, 576611546, 2387784026, 6790697458, 28130266234, 117517748130, 334241631914, 1392238253906, 5834290389498, 16600291514074, 69280767349754

Offset

1,1

Comments

Column 2 of A251829

Links

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

Formula

Empirical: a(n) = a(n-1) +14*a(n-2) +94*a(n-3) -158*a(n-4) -1445*a(n-5) -2492*a(n-6) +9233*a(n-7) +48962*a(n-8) +5034*a(n-9) -242838*a(n-10) -600349*a(n-11) +613035*a(n-12) +2605838*a(n-13) -360082*a(n-14) -6715786*a(n-15) +2529996*a(n-16) +63651804*a(n-17) -9595652*a(n-18) -284913112*a(n-19) -459860504*a(n-20) +476236808*a(n-21) +2249658800*a(n-22) +1069882400*a(n-23) -2543610400*a(n-24) -6852708800*a(n-25) -770009600*a(n-26) +5089939200*a(n-27) +8372160000*a(n-28) +1342720000*a(n-29) -3517440000*a(n-30) -4736000000*a(n-31) -512000000*a(n-32) +1024000000*a(n-33) for n>36

Example

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

Crossrefs

Sequence in context: A250671 A179139 A014887 * A031822 A288894 A289563

Adjacent sequences: A251820 A251821 A251822 * A251824 A251825 A251826

Keyword

nonn

Author

R. H. Hardin, Dec 09 2014

Status

approved