login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A233217
T(n,k)=Number of nXk 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order
14
1, 2, 3, 6, 23, 11, 23, 376, 452, 48, 99, 7222, 35446, 10313, 236, 452, 147019, 3054973, 3638416, 249062, 1248, 2136, 3054973, 268289572, 1340889772, 380283286, 6147803, 6896, 10313, 63927526, 23644611625, 496475792293, 591021089923, 39892988056
OFFSET
1,2
COMMENTS
Table starts
....1.........2.............6.................23.....................99
....3........23...........376...............7222.................147019
...11.......452.........35446............3054973..............268289572
...48.....10313.......3638416.........1340889772...........496475792293
..236....249062.....380283286.......591021089923........919538740854193
.1248...6147803...39892988056....260625046992322....1703198747507336644
.6896.152986472.4187991850726.114934898294104873.3154729081272072714436
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 12*a(n-1) -44*a(n-2) +48*a(n-3)
k=2: a(n) = 35*a(n-1) -259*a(n-2) +225*a(n-3)
k=3: a(n) = 127*a(n-1) -2331*a(n-2) +2205*a(n-3)
k=4: a(n) = 491*a(n-1) -22099*a(n-2) +21609*a(n-3)
k=5: a(n) = 1975*a(n-1) -228357*a(n-2) +1804281*a(n-3) -4170978*a(n-4) +2593080*a(n-5)
k=6: [order 7]
k=7: [order 11]
Empirical for row n:
n=1: a(n) = 9*a(n-1) -23*a(n-2) +15*a(n-3)
n=2: a(n) = 29*a(n-1) -175*a(n-2) +147*a(n-3) for n>4
n=3: a(n) = 111*a(n-1) -2128*a(n-2) +10532*a(n-3) -17559*a(n-4) +9045*a(n-5) for n>7
n=4: [order 9] for n>12
n=5: [order 19] for n>23
n=6: [order 42] for n>47
EXAMPLE
Some solutions for n=3 k=4
..0..0..0..1....0..0..0..1....0..0..0..1....0..0..0..1....0..0..0..1
..2..1..2..1....0..1..5..1....0..2..2..1....2..0..0..0....0..2..1..3
..2..0..2..2....1..5..1..0....4..0..1..0....0..1..3..5....2..0..0..2
CROSSREFS
Column 1 is A233162(n+1)
Row 1 is A233106
Sequence in context: A303584 A261014 A000616 * A261963 A183179 A018300
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Dec 06 2013
STATUS
approved