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A252294 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 3 6 or 7 1
943, 856, 976, 1481, 2079, 3265, 5676, 10939, 21842, 45450, 94429, 201843, 436593, 950880, 2077933, 4556174, 9995748, 21960671, 48283531, 106217277, 233735492, 514456023, 1132428018, 2493020906, 5488771613, 12085003787, 26609253669 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A252295

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +a(n-2) +2*a(n-3) -3*a(n-4) -7*a(n-5) -3*a(n-6) -13*a(n-7) +10*a(n-8) +12*a(n-9) +20*a(n-10) +20*a(n-11) +18*a(n-12) +12*a(n-13) -58*a(n-14) -84*a(n-15) -26*a(n-16) +46*a(n-17) +62*a(n-18) +26*a(n-19) -28*a(n-20) -40*a(n-21) -16*a(n-22) +16*a(n-23) +24*a(n-24) +8*a(n-25) for n>30

EXAMPLE

Some solutions for n=4

..2..2..1....3..1..0....1..1..2....3..1..1....1..2..2....3..3..3....0..2..2

..1..3..1....1..0..3....2..1..1....2..0..3....3..3..2....3..3..3....1..3..1

..1..0..3....1..3..1....1..2..2....0..3..1....0..0..1....3..3..3....3..0..1

..3..2..0....2..2..1....2..2..1....2..2..0....2..1..1....2..3..3....0..1..3

..0..3..2....2..0..2....1..1..2....2..0..3....2..3..3....3..3..3....2..3..0

..1..0..3....0..2..2....2..1..1....1..2..2....0..1..0....3..3..3....3..0..2

CROSSREFS

Sequence in context: A104302 A228382 A252295 * A268268 A106431 A234485

Adjacent sequences:  A252291 A252292 A252293 * A252295 A252296 A252297

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 16 2014

STATUS

approved

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Last modified September 19 23:31 EDT 2019. Contains 327207 sequences. (Running on oeis4.)