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A251292 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 or main diagonally 9
9, 22, 22, 52, 71, 52, 125, 219, 219, 125, 297, 701, 822, 701, 297, 710, 2193, 3390, 3390, 2193, 710, 1691, 6980, 12954, 18924, 12954, 6980, 1691, 4036, 21966, 52474, 94706, 94706, 52474, 21966, 4036, 9621, 69681, 202882, 518711, 577942, 518711, 202882 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

.....9.....22.......52.......125........297..........710..........1691

....22.....71......219.......701.......2193.........6980.........21966

....52....219......822......3390......12954........52474........202882

...125....701.....3390.....18924......94706.......518711.......2645966

...297...2193....12954.....94706.....577942......4109933......25654154

...710...6980....52474....518711....4109933.....39473392.....322933003

..1691..21966...202882...2645966...25654154....322933003....3232216177

..4036..69681...813336..14292754..178853600...3029148345...39571705178

..9621.219860..3168621..73763850.1134888362..25329125380..405845538185

.22951.696284.12623928.394839392.7800498387.233446638426.4863503527792

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..544

FORMULA

Empirical for column k:

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

k=2: a(n) = 2*a(n-1) +7*a(n-2) -9*a(n-3) -7*a(n-4) +7*a(n-5) for n>6

k=3: [order 11]

k=4: [order 19]

k=5: [order 33] for n>34

k=6: [order 58] for n>59

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

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

CROSSREFS

Sequence in context: A342409 A329007 A250729 * A177458 A228009 A330477

Adjacent sequences:  A251289 A251290 A251291 * A251293 A251294 A251295

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Dec 01 2014

STATUS

approved

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Last modified October 26 04:27 EDT 2021. Contains 348256 sequences. (Running on oeis4.)