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Revision History for A295051

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T(n,k) = Number of n X k 0..1 arrays with each 1 horizontally or vertically adjacent to 0 or 2 1's.
(history; published version)
#6 by Wesley Ivan Hurt at Thu Nov 03 21:51:55 EDT 2022
STATUS

editing

approved

#5 by Wesley Ivan Hurt at Thu Nov 03 21:51:50 EDT 2022
NAME

T(n,k) = Number of nXk n X k 0..1 arrays with each 1 horizontally or vertically adjacent to 0 or 2 1s1's.

FORMULA

k=1: a(n) = a(n-1) +a(n-2).

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

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

k=4: [order 18].

k=5: [order 49].

EXAMPLE

Some solutions for n=5 , k=4

STATUS

approved

editing

#4 by R. H. Hardin at Mon Nov 13 06:42:46 EST 2017
STATUS

editing

approved

#3 by R. H. Hardin at Mon Nov 13 06:42:41 EST 2017
LINKS

R. H. Hardin, <a href="/A295051/b295051.txt">Table of n, a(n) for n = 1..312</a>

#2 by R. H. Hardin at Mon Nov 13 06:42:10 EST 2017
NAME

allocated for R. H. Hardin

T(n,k)=Number of nXk 0..1 arrays with each 1 horizontally or vertically adjacent to 0 or 2 1s.

DATA

2, 3, 3, 5, 8, 5, 8, 19, 19, 8, 13, 48, 72, 48, 13, 21, 120, 270, 270, 120, 21, 34, 299, 1027, 1569, 1027, 299, 34, 55, 747, 3879, 9045, 9045, 3879, 747, 55, 89, 1865, 14691, 52199, 79855, 52199, 14691, 1865, 89, 144, 4656, 55589, 301306, 700972, 700972, 301306

OFFSET

1,1

COMMENTS

Table starts

..2....3......5........8........13..........21............34.............55

..3....8.....19.......48.......120.........299...........747...........1865

..5...19.....72......270......1027........3879.........14691..........55589

..8...48....270.....1569......9045.......52199........301306........1739181

.13..120...1027.....9045.....79855......700972.......6171389.......54282231

.21..299...3879....52199....700972.....9388654.....125887202.....1687776548

.34..747..14691...301306...6171389...125887202....2573527520....52573942625

.55.1865..55589..1739181..54282231..1687776548...52573942625..1637027372706

.89.4656.210418.10038808.477606439.22627774940.1074298644657.50976777525816

FORMULA

Empirical for column k:

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

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

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

k=4: [order 18]

k=5: [order 49]

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 1 is A000045(n+2).

KEYWORD

allocated

nonn,tabl

AUTHOR

R. H. Hardin, Nov 13 2017

STATUS

approved

editing

#1 by R. H. Hardin at Mon Nov 13 06:27:45 EST 2017
NAME

allocated for R. H. Hardin

KEYWORD

allocated

STATUS

approved