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A204491 Number of (n+2)X9 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly one way, and new values 0..1 introduced in row major order 1
35172, 28743, 50897, 90942, 168567, 331723, 658793, 1277695, 2455575, 4765823, 9372187, 18590575, 37054835, 74180927, 148918284, 299395145, 602639784, 1214402311, 2449573637, 4945318628, 9990612579, 20196844929, 40859216212 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A204492

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +9*a(n-3) -5*a(n-4) -10*a(n-5) -7*a(n-6) -28*a(n-7) +16*a(n-8) -9*a(n-9) +34*a(n-10) +3*a(n-11) +4*a(n-12) +26*a(n-13) -13*a(n-14) +14*a(n-15) -26*a(n-16) -3*a(n-17) -10*a(n-18) -2*a(n-19) +6*a(n-20) -6*a(n-21) +3*a(n-22) +6*a(n-24) -3*a(n-25) for n>37

EXAMPLE

Some solutions for n=3

..0..1..1..0..0..0..1..0..1....0..0..1..0..0..1..0..1..1

..1..1..0..1..0..1..0..0..0....0..1..0..0..1..0..1..0..1

..0..0..0..0..1..1..1..1..0....1..1..1..1..1..1..0..1..0

..0..1..1..0..0..0..1..0..1....0..0..1..0..0..1..1..0..1

..1..1..0..1..0..1..0..0..0....0..1..0..0..1..0..1..1..1

CROSSREFS

Sequence in context: A234988 A075831 A213805 * A085545 A031855 A186567

Adjacent sequences:  A204488 A204489 A204490 * A204492 A204493 A204494

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 15 2012

STATUS

approved

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Last modified May 21 18:53 EDT 2019. Contains 323444 sequences. (Running on oeis4.)