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A295379
T(n,k)=Number of nXk 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 2 or 4 1s.
7
2, 3, 3, 5, 8, 5, 8, 19, 19, 8, 13, 48, 74, 48, 13, 21, 120, 278, 278, 120, 21, 34, 299, 1067, 1634, 1067, 299, 34, 55, 747, 4071, 9507, 9507, 4071, 747, 55, 89, 1865, 15557, 55643, 85310, 55643, 15557, 1865, 89, 144, 4656, 59407, 325134, 761795, 761795, 325134
OFFSET
1,1
COMMENTS
Table starts
..2....3......5........8........13..........21............34.............55
..3....8.....19.......48.......120.........299...........747...........1865
..5...19.....74......278......1067........4071.........15557..........59407
..8...48....278.....1634......9507.......55643........325134........1900380
.13..120...1067.....9507.....85310......761795.......6819658.......60996884
.21..299...4071....55643....761795....10437240.....142860055.....1956512289
.34..747..15557...325134...6819658...142860055....2995361770....62765357574
.55.1865..59407..1900380..60996884..1956512289...62765357574..2013609204094
.89.4656.226944.11107738.545729054.26790134422.1315649551906.64595519660126
LINKS
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: [order 10]
k=4: [order 25]
k=5: [order 70]
EXAMPLE
Some solutions for n=5 k=4
..0..0..0..0. .1..0..1..0. .0..0..1..0. .0..0..0..1. .0..0..1..0
..0..1..0..0. .0..0..0..0. .1..1..0..1. .1..0..0..0. .1..0..0..0
..1..0..0..1. .0..0..0..1. .1..1..1..0. .0..0..0..0. .0..1..0..0
..0..0..1..0. .1..1..0..0. .0..1..1..1. .0..0..0..1. .1..0..0..1
..0..1..0..0. .1..1..0..1. .0..0..1..1. .0..0..1..0. .0..1..0..0
CROSSREFS
Column 1 is A000045(n+2).
Column 2 is A295045.
Sequence in context: A296335 A296635 A295051 * A295352 A295606 A154690
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Nov 21 2017
STATUS
approved