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A231031 T(n,k)=Number of nXk 0..2 arrays x(i,j) with each element horizontally, vertically or antidiagonally next to at least one element with value (x(i,j)+1) mod 3 and at least one element with value (x(i,j)-1) mod 3, and upper left element zero 8
0, 0, 0, 0, 2, 0, 0, 12, 12, 0, 0, 62, 60, 62, 0, 0, 344, 1074, 1074, 344, 0, 0, 1864, 12400, 43566, 12400, 1864, 0, 0, 10162, 162288, 1444702, 1444702, 162288, 10162, 0, 0, 55324, 2049324, 50554618, 124446770, 50554618, 2049324, 55324, 0, 0, 301278 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.0.....0........0...........0..............0..................0

.0.....2.......12..........62............344...............1864

.0....12.......60........1074..........12400.............162288

.0....62.....1074.......43566........1444702...........50554618

.0...344....12400.....1444702......124446770........11542542126

.0..1864...162288....50554618....11542542126......2846678305070

.0.10162..2049324..1740086452..1050541512334....688099769580280

.0.55324.26149710.60169326764.96084401660280.167200150832484832

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..127

FORMULA

Empirical for column k:

k=2: a(n) = 4*a(n-1) +8*a(n-2) -4*a(n-4) +a(n-5)

k=3: [order 28]

EXAMPLE

Some solutions for n=3 k=4

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

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

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

CROSSREFS

Sequence in context: A289651 A302751 A244139 * A061848 A193294 A231049

Adjacent sequences:  A231028 A231029 A231030 * A231032 A231033 A231034

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 03 2013

STATUS

approved

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Last modified November 13 00:25 EST 2019. Contains 329083 sequences. (Running on oeis4.)