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A204637 Number of (n+2) X 5 0..3 arrays with every 3 X 3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..3 introduced in row major order. 1
1781, 5974, 248, 933, 760, 2517, 9750, 28856, 108520, 412247, 1538786, 5831457, 22111228, 83757474, 317540856, 1203895697, 4564096372, 17303777693, 65603619578, 248721544020, 942974882152, 3575089249203, 13554190415694 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A204642.

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) -3*a(n-2) -4*a(n-3) -12*a(n-4) +12*a(n-5) +21*a(n-6) -9*a(n-7) -9*a(n-8) for n>10.

Empirical g.f.: x*(1781 - 2931*x - 24279*x^2 + 24739*x^3 + 42107*x^4 + 52824*x^5 - 102936*x^6 - 110508*x^7 + 66069*x^8 + 52704*x^9) / ((1 - x)*(1 - x - x^2)*(1 - 3*x - 3*x^2)*(1 - 3*x^3)). - Colin Barker, Jun 08 2018

EXAMPLE

Some solutions for n=3:

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

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

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

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

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

CROSSREFS

Cf. A204642.

Sequence in context: A237906 A187524 A253057 * A023088 A251086 A255157

Adjacent sequences:  A204634 A204635 A204636 * A204638 A204639 A204640

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 17 2012

STATUS

approved

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Last modified January 19 23:38 EST 2022. Contains 350467 sequences. (Running on oeis4.)