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A252345 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 3 5 6 or 8 and every 3X3 diagonal and antidiagonal sum equal to 0 3 5 6 or 8 1
562, 798, 1331, 2176, 4013, 7109, 12670, 23051, 42677, 76847, 144622, 269725, 498250, 941982, 1789811, 3325857, 6370800, 12178628, 22845814, 43963436, 84669873, 159459251, 308410785, 596046949, 1127115248, 2185125529, 4236058398 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A252352

LINKS

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

FORMULA

Empirical: a(n) = -a(n-1) +3*a(n-2) +24*a(n-3) +20*a(n-4) -59*a(n-5) -225*a(n-6) -152*a(n-7) +423*a(n-8) +1045*a(n-9) +574*a(n-10) -1357*a(n-11) -2485*a(n-12) -1178*a(n-13) +1910*a(n-14) +2505*a(n-15) +911*a(n-16) -567*a(n-17) +830*a(n-18) +1299*a(n-19) -1040*a(n-20) -4171*a(n-21) -3547*a(n-22) +415*a(n-23) +3286*a(n-24) +2940*a(n-25) +642*a(n-26) -731*a(n-27) -919*a(n-28) -403*a(n-29) -91*a(n-30) +53*a(n-31) +33*a(n-32) +14*a(n-33) for n>39

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A139089 A202562 A252352 * A121508 A252344 A250976

Adjacent sequences:  A252342 A252343 A252344 * A252346 A252347 A252348

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 16 2014

STATUS

approved

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Last modified May 17 12:01 EDT 2021. Contains 343971 sequences. (Running on oeis4.)