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A231539 Number of nX3 0..1 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors 1
4, 20, 116, 589, 3001, 15644, 81179, 420243, 2177937, 11287977, 58494710, 303132340, 1570918959, 8140881877, 42188034539, 218628945511, 1132989453013, 5871432030067, 30427217632524, 157681390442587, 817144077007238 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A231544

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) +34*a(n-3) -67*a(n-4) +86*a(n-5) -79*a(n-6) +14*a(n-7) +47*a(n-8) -66*a(n-9) +15*a(n-10) -105*a(n-11) +121*a(n-12) +24*a(n-13) -40*a(n-14) -56*a(n-15) +2*a(n-16) +43*a(n-17) -11*a(n-18) -15*a(n-19) -6*a(n-20) +2*a(n-21) +a(n-22)

EXAMPLE

Some solutions for n=7

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A341919 A192924 A258664 * A106567 A077445 A085458

Adjacent sequences:  A231536 A231537 A231538 * A231540 A231541 A231542

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 10 2013

STATUS

approved

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Last modified June 26 00:12 EDT 2022. Contains 354870 sequences. (Running on oeis4.)