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.

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

Author

R. H. Hardin, Nov 30 2014

Keywords

• nonn
• tabl

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

Examples

			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
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..364

Crossrefs

Column 1 is A048573(n+2).

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)