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A304676 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero. 7
1, 1, 1, 1, 4, 1, 1, 7, 7, 1, 1, 13, 13, 13, 1, 1, 26, 23, 23, 26, 1, 1, 49, 45, 56, 45, 49, 1, 1, 99, 131, 199, 199, 131, 99, 1, 1, 194, 337, 598, 897, 598, 337, 194, 1, 1, 387, 883, 1950, 3525, 3525, 1950, 883, 387, 1, 1, 773, 2389, 6588, 15544, 20932, 15544, 6588, 2389 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.1...1....1.....1......1.......1........1.........1...........1............1

.1...4....7....13.....26......49.......99.......194.........387..........773

.1...7...13....23.....45.....131......337.......883........2389.........6599

.1..13...23....56....199.....598.....1950......6588.......21871........72947

.1..26...45...199....897....3525....15544.....68896......310438......1387613

.1..49..131...598...3525...20932...122388....711362.....4369285.....26155072

.1..99..337..1950..15544..122388...930123...7208807....57718628....454436233

.1.194..883..6588..68896..711362..7208807..73484449...779364745...8098139458

.1.387.2389.21871.310438.4369285.57718628.779364745.11082127004.153249721883

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..197

FORMULA

Empirical for column k:

k=1: a(n) = a(n-1)

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

k=3: [order 18] for n>19

k=4: [order 70] for n>71

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 2 is A304004.

Sequence in context: A305360 A304952 A316620 * A316123 A146771 A073697

Adjacent sequences:  A304673 A304674 A304675 * A304677 A304678 A304679

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, May 16 2018

STATUS

approved

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Last modified August 18 13:12 EDT 2019. Contains 326100 sequences. (Running on oeis4.)