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A199144 Number of nX3 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors 1
1, 13, 132, 2453, 42420, 794416, 14511531, 268456338, 4940928443, 91146218920, 1679743067872, 30969409565822, 570877041856787, 10524153072061784, 194006638767664141, 3576453618832667684, 65930406443303698229 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A199149

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 14*a(n-1) +120*a(n-2) -646*a(n-3) -1320*a(n-4) +3562*a(n-5) +12682*a(n-6) +1896*a(n-7) -76623*a(n-8) +36670*a(n-9) +19724*a(n-10) -245388*a(n-11) +53233*a(n-12) +2738818*a(n-13) -138967*a(n-14) -11411168*a(n-15) +3626519*a(n-16) +17979294*a(n-17) -10633666*a(n-18) -27553810*a(n-19) +19090457*a(n-20) +20077526*a(n-21) -32139160*a(n-22) +46609580*a(n-23) +115127457*a(n-24) +146403730*a(n-25) +50426678*a(n-26) -122760336*a(n-27) -143444310*a(n-28) -587979162*a(n-29) -679787397*a(n-30) -166474764*a(n-31) -212565465*a(n-32) +6372918*a(n-33) +256248603*a(n-34) +47278566*a(n-35) -708588*a(n-36) -12754584*a(n-37) for n>38

EXAMPLE

Some solutions for n=4

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

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

..3..3..2....2..2..0....2..2..0....2..3..2....1..0..3....1..1..0....0..0..1

..1..1..1....3..3..3....2..0..0....2..3..2....1..0..3....2..2..0....0..1..1

CROSSREFS

Sequence in context: A037715 A037617 A295603 * A198664 A332243 A081042

Adjacent sequences:  A199141 A199142 A199143 * A199145 A199146 A199147

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 03 2011

STATUS

approved

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Last modified December 1 04:32 EST 2021. Contains 349426 sequences. (Running on oeis4.)