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A204635 Number of (n+2)X3 0..3 arrays with every 3X3 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
124, 405, 1781, 4246, 16855, 65096, 144255, 651750, 2480147, 6826114, 28519709, 102468425, 302547337, 1231849272, 4512654559, 14517240364, 56492934539, 205115926577, 698714375439, 2693352796243, 9877987196219, 34884036107922 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A204642

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) -14*a(n-2) +32*a(n-3) -178*a(n-4) +518*a(n-5) -1017*a(n-6) +609*a(n-7) -2461*a(n-8) +25287*a(n-9) -43874*a(n-10) +6054*a(n-11) -25095*a(n-12) +64297*a(n-13) +152172*a(n-14) -435728*a(n-15) +555156*a(n-16) -501972*a(n-17) +253956*a(n-18) +255660*a(n-19) -906516*a(n-20) +522900*a(n-21) +294048*a(n-22) +45792*a(n-23) -362448*a(n-24) +434592*a(n-25) -860544*a(n-26) +715392*a(n-27) -186624*a(n-28) for n>29

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A045250 A258931 A204642 * A102589 A189812 A230830

Adjacent sequences:  A204632 A204633 A204634 * A204636 A204637 A204638

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 17 2012

STATUS

approved

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Last modified October 20 21:31 EDT 2021. Contains 348119 sequences. (Running on oeis4.)