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A221661 Equals one maps: number of 3Xn binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal and antidiagonal neighbors in a random 0..2 3Xn array 1
1, 32, 323, 3322, 29939, 254682, 2078316, 16737048, 134125927, 1073540636, 8589440133, 68718137608, 549750960379, 4398021285748, 35184200917302, 281473676944626, 2251789571402135, 18014316922806328, 144114536170600217 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 3 of A221660

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..197

FORMULA

Empirical: a(n) = 10*a(n-1) -10*a(n-2) -58*a(n-3) +65*a(n-4) +144*a(n-5) -162*a(n-6) -316*a(n-7) +519*a(n-8) +878*a(n-9) -1156*a(n-10) -1674*a(n-11) +2225*a(n-12) +2008*a(n-13) -5440*a(n-14) -4248*a(n-15) +4872*a(n-16) +4504*a(n-17) -7440*a(n-18) -4896*a(n-19) +10992*a(n-20) +4224*a(n-21) -432*a(n-22) +4032*a(n-23) -4032*a(n-24) -4608*a(n-25) for n>50

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A083468 A125395 A126553 * A221064 A224161 A224412

Adjacent sequences:  A221658 A221659 A221660 * A221662 A221663 A221664

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 21 2013

STATUS

approved

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Last modified May 28 17:37 EDT 2020. Contains 334684 sequences. (Running on oeis4.)