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A204480 Number of (n+2)X7 0..3 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly three ways, and new values 0..3 introduced in row major order 1
7191, 8114, 2632, 3270, 6494, 11338, 35990, 132258, 473380, 1786812, 6773680, 25609458, 97080840, 368071380, 1395260888, 5289809914, 20055230346, 76034546154, 288268775378, 1092910015022, 4143534627852, 15709332220768 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A204483

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +a(n-2) -2*a(n-3) -19*a(n-4) -4*a(n-5) +21*a(n-6) +24*a(n-7) +3*a(n-8) -18*a(n-9) -9*a(n-10) for n>13

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A143193 A064979 A348807 * A035906 A190114 A239566

Adjacent sequences:  A204477 A204478 A204479 * A204481 A204482 A204483

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 15 2012

STATUS

approved

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Last modified December 2 23:22 EST 2021. Contains 349445 sequences. (Running on oeis4.)