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A280313 T(n,k)=Number of nXk 0..2 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. 5
0, 0, 0, 0, 0, 0, 1, 15, 15, 1, 2, 222, 788, 222, 2, 9, 2348, 20274, 20274, 2348, 9, 34, 21302, 415198, 1047790, 415198, 21302, 34, 124, 176125, 7506237, 43973846, 43973846, 7506237, 176125, 124, 432, 1370378, 125467047, 1638451216, 3802506340 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,8
COMMENTS
Table starts
....0........0............0..............1................2................9
....0........0...........15............222.............2348............21302
....0.......15..........788..........20274...........415198..........7506237
....1......222........20274........1047790.........43973846.......1638451216
....2.....2348.......415198.......43973846.......3802506340.....292789164101
....9....21302......7506237.....1638451216.....292789164101...46670265882656
...34...176125....125467047....56602534187...20928606452792.6910403433332994
..124..1370378...1986983748..1855013487412.1420117779715304
..432.10206549..30245976536.58477471703834
.1464.73563740.446674283782
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 6*a(n-1) -6*a(n-2) -16*a(n-3) +12*a(n-4) +24*a(n-5) +8*a(n-6) for n>10
k=2: [order 12]
k=3: [order 36] for n>38
EXAMPLE
Some solutions for n=3 k=4
..0..0..1..2. .0..1..2..1. .0..0..1..1. .0..1..0..2. .0..0..0..1
..1..0..2..0. .2..1..2..0. .2..0..2..2. .1..1..0..1. .2..2..2..1
..2..0..2..0. .0..2..2..2. .2..2..1..0. .0..2..0..1. .1..1..0..0
CROSSREFS
Column 2 is A279530.
Sequence in context: A048294 A248391 A201345 * A291369 A069785 A290850
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Dec 31 2016
STATUS
approved

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Last modified March 29 04:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)