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A296990 T(n,k)=Number of nXk 0..1 arrays with each 1 adjacent to 3, 4 or 5 king-move neighboring 1s. 8
1, 1, 1, 1, 2, 1, 1, 4, 4, 1, 1, 7, 14, 7, 1, 1, 14, 28, 28, 14, 1, 1, 33, 98, 74, 98, 33, 1, 1, 77, 447, 440, 440, 447, 77, 1, 1, 185, 1653, 2514, 5487, 2514, 1653, 185, 1, 1, 460, 6507, 12601, 65694, 65694, 12601, 6507, 460, 1, 1, 1148, 27374, 71009, 639327, 1621832 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

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

.1...2.....4......7.......14..........33...........77.............185

.1...4....14.....28.......98.........447.........1653............6507

.1...7....28.....74......440........2514........12601...........71009

.1..14....98....440.....5487.......65694.......639327.........7181983

.1..33...447...2514....65694.....1621832.....26724927.......546305423

.1..77..1653..12601...639327....26724927....702794334.....24416753991

.1.185..6507..71009..7181983...546305423..24416753991...1529176981800

.1.460.27374.401521.81977832.11821168013.892243428330.100472530942946

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..180

FORMULA

Empirical for column k:

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

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

k=3: [order 20]

k=4: [order 43]

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Sequence in context: A104382 A086629 A203948 * A156184 A056588 A126770

Adjacent sequences:  A296987 A296988 A296989 * A296991 A296992 A296993

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Dec 22 2017

STATUS

approved

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Last modified December 8 20:37 EST 2021. Contains 349596 sequences. (Running on oeis4.)