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A251149
T(n,k) = Number of (n+1) X (k+1) 0..2 arrays with every 2 X 2 subblock summing to 4 and no 2 X 2 subblock having exactly two nonzero entries.
8
13, 27, 27, 53, 49, 53, 107, 87, 87, 107, 213, 161, 143, 161, 213, 427, 299, 247, 247, 299, 427, 853, 565, 433, 401, 433, 565, 853, 1707, 1075, 777, 667, 667, 777, 1075, 1707, 3413, 2065, 1413, 1141, 1061, 1141, 1413, 2065, 3413, 6827, 3991, 2607, 1987, 1743
OFFSET
1,1
COMMENTS
Table starts:
...13...27...53...107...213...427...853..1707..3413...6827..13653..27307..54613
...27...49...87...161...299...565..1075..2065..3991...7761..15163..29749..58563
...53...87..143...247...433...777..1413..2607..4863...9167..17433..33417..64493
..107..161..247...401...667..1141..1987..3521..6327..11521..21227..39541..74387
..213..299..433...667..1061..1743..2925..5003..8689..15307..27317..49359..90237
..427..565..777..1141..1743..2763..4491..7453.12569..21501..37255..65355.116035
..853.1075.1413..1987..2925..4491..7101.11491.18917..31587..53389..91275.157789
.1707.2065.2607..3521..5003..7453.11491.18193.29359..48081..79675.133405.225555
.3413.3991.4863..6327..8689.12569.18917.29359.46575..75087.122521.201881.335501
.6827.7761.9167.11521.15307.21501.31587.48081.75087.119441.192507.313341.514067
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +2*a(n-2)
k=2: a(n) = 3*a(n-1) -5*a(n-3) +a(n-4) +2*a(n-5)
k=3: a(n) = 3*a(n-1) -5*a(n-3) +a(n-4) +2*a(n-5)
k=4: a(n) = 3*a(n-1) -5*a(n-3) +a(n-4) +2*a(n-5)
k=5: a(n) = 3*a(n-1) -5*a(n-3) +a(n-4) +2*a(n-5)
k=6: a(n) = 3*a(n-1) -5*a(n-3) +a(n-4) +2*a(n-5)
k=7: a(n) = 3*a(n-1) -5*a(n-3) +a(n-4) +2*a(n-5)
EXAMPLE
Some solutions for n=4, k=4:
..0..1..0..2..1....1..0..1..1..1....1..0..1..1..2....2..1..2..1..1
..1..2..1..1..0....1..2..1..1..1....1..2..1..1..0....0..1..0..1..1
..1..0..1..1..2....1..0..1..1..1....0..1..0..2..1....1..2..1..2..0
..1..2..1..1..0....1..2..1..1..1....1..2..1..1..0....0..1..0..1..1
..1..0..1..1..2....1..0..1..1..1....0..1..0..2..1....2..1..2..1..1
CROSSREFS
Column 1 is A048573(n+2).
Sequence in context: A098961 A033897 A005029 * A293787 A041330 A041765
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Nov 30 2014
STATUS
approved