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A251784 Number of (n+2)X(1+2) 0..3 arrays with no row, column, diagonal or antidiagonal in any 3X3 subblock summing to 2 3 6 or 7 1
1280, 1664, 3072, 6144, 11834, 22632, 44792, 86988, 170432, 342826, 673546, 1333808, 2714614, 5407074, 10855306, 22352610, 45191680, 92075992, 191833122, 393688208, 813894868, 1714886756, 3570500704, 7482636226, 15926322646 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A251791

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +2*a(n-2) +14*a(n-3) -29*a(n-4) -39*a(n-5) -60*a(n-6) +103*a(n-7) +261*a(n-8) +219*a(n-9) +54*a(n-10) -679*a(n-11) -1209*a(n-12) -512*a(n-13) +491*a(n-14) +1546*a(n-15) +1721*a(n-16) +293*a(n-17) -756*a(n-18) -463*a(n-19) +513*a(n-20) +1705*a(n-21) +1590*a(n-22) -297*a(n-23) -1862*a(n-24) -1774*a(n-25) -161*a(n-26) +1644*a(n-27) +1852*a(n-28) +334*a(n-29) -1340*a(n-30) -1888*a(n-31) -1090*a(n-32) +44*a(n-33) +608*a(n-34) +484*a(n-35) +32*a(n-36) -352*a(n-37) -424*a(n-38) -336*a(n-39) -192*a(n-40) -48*a(n-41) for n>50

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A251887 A251894 A251791 * A234315 A251783 A224645

Adjacent sequences:  A251781 A251782 A251783 * A251785 A251786 A251787

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 08 2014

STATUS

approved

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Last modified January 19 03:18 EST 2020. Contains 331031 sequences. (Running on oeis4.)