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A251258 T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with every 2X2 subblock having a single 1 or two 1s on the same edge 9
8, 18, 18, 38, 56, 38, 84, 150, 150, 84, 180, 446, 464, 446, 180, 394, 1232, 1770, 1770, 1232, 394, 850, 3602, 5680, 9130, 5680, 3602, 850, 1852, 10108, 21088, 38332, 38332, 21088, 10108, 1852, 4008, 29272, 69270, 192442, 185620, 192442, 69270, 29272, 4008 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

....8.....18......38.......84........180.........394..........850

...18.....56.....150......446.......1232........3602........10108

...38....150.....464.....1770.......5680.......21088........69270

...84....446....1770.....9130......38332......192442.......836546

..180...1232....5680....38332.....185620.....1215600......6080510

..394...3602...21088...192442....1215600....10753448.....71459218

..850..10108...69270...836546....6080510....71459218....539961360

.1852..29272..252226..4112126...38748690...612889014...6151714502

.4008..82854..842160.18298862..198765264..4229034766..47962536500

.8714.238640.3024532.88585834.1238605998.35355603854.531311887046

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..611

FORMULA

Empirical for column k:

k=1: a(n) = a(n-1) +3*a(n-2) -a(n-3)

k=2: a(n) = 3*a(n-1) +4*a(n-2) -14*a(n-3) +3*a(n-4) +3*a(n-5)

k=3: a(n) = a(n-1) +13*a(n-2) -7*a(n-3) -32*a(n-4) +8*a(n-5) +10*a(n-6)

k=4: [order 12]

k=5: [order 17]

k=6: [order 31]

k=7: [order 49]

EXAMPLE

Some solutions for n=4 k=4

..0..1..0..0..0....0..0..1..0..0....0..0..1..0..1....1..0..1..1..0

..0..1..0..1..1....1..0..1..0..1....1..0..0..0..0....1..0..0..0..0

..0..0..0..0..0....0..0..0..0..0....0..0..1..0..1....1..0..1..1..0

..1..1..1..0..1....0..1..0..1..0....1..0..1..0..0....1..0..0..0..0

..0..0..0..0..1....0..1..0..1..0....0..0..1..0..1....1..0..1..1..0

CROSSREFS

Sequence in context: A322031 A196207 A196474 * A101241 A307973 A031258

Adjacent sequences:  A251255 A251256 A251257 * A251259 A251260 A251261

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Dec 01 2014

STATUS

approved

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Last modified October 28 12:04 EDT 2021. Contains 348329 sequences. (Running on oeis4.)