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A220316 Equals two maps: number of nX2 binary arrays indicating the locations of corresponding elements equal to exactly two of their king-move neighbors in a random 0..2 nX2 array 1
1, 5, 24, 89, 389, 1566, 6401, 25704, 103047, 411453, 1640962, 6538036, 26037222, 103664093, 412658625, 1642555969, 6537717638, 26020883563, 103564418265, 412188609650, 1640510914951, 6529219819790, 25986198727161, 103424615577923 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 2 of A220319

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +6*a(n-2) -22*a(n-3) -15*a(n-4) +10*a(n-5) +56*a(n-6) +46*a(n-7) -112*a(n-8) -84*a(n-9) -67*a(n-10) +358*a(n-11) +277*a(n-12) -168*a(n-13) -638*a(n-14) -162*a(n-15) +664*a(n-16) +408*a(n-17) +180*a(n-18) -8*a(n-19) +76*a(n-20) -264*a(n-21) +96*a(n-22)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A270682 A272420 A089095 * A220339 A158499 A074085

Adjacent sequences:  A220313 A220314 A220315 * A220317 A220318 A220319

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 10 2012

STATUS

approved

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Last modified October 4 01:04 EDT 2022. Contains 357237 sequences. (Running on oeis4.)