login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A299937
T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.
7
0, 1, 1, 1, 4, 1, 2, 18, 18, 2, 3, 64, 130, 64, 3, 5, 236, 902, 902, 236, 5, 8, 888, 6243, 11212, 6243, 888, 8, 13, 3336, 43375, 144072, 144072, 43375, 3336, 13, 21, 12512, 300901, 1858165, 3441754, 1858165, 300901, 12512, 21, 34, 46928, 2088188
OFFSET
1,5
COMMENTS
Table starts
..0.....1........1..........2.............3...............5.................8
..1.....4.......18.........64...........236.............888..............3336
..1....18......130........902..........6243...........43375............300901
..2....64......902......11212........144072.........1858165..........23924290
..3...236.....6243.....144072.......3441754........82403876........1969988474
..5...888....43375....1858165......82403876......3664429516......162678451993
..8..3336...300901...23924290....1969988474....162678451993....13409569414628
.13.12512..2088188..308062375...47097894761...7222553677769..1105467648686714
.21.46928.14490885.3966828615.1126027901118.320673103163046.91135851756212849
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = 4*a(n-1) -2*a(n-2) +4*a(n-3) for n>4
k=3: [order 10] for n>11
k=4: [order 33] for n>34
EXAMPLE
Some solutions for n=5 k=4
..0..0..0..0. .0..0..1..0. .0..0..1..1. .0..0..1..0. .0..0..1..1
..1..0..1..0. .0..1..0..1. .1..0..1..1. .1..1..1..0. .0..1..1..0
..0..1..1..1. .1..0..0..0. .1..1..0..0. .1..0..0..1. .1..0..0..0
..1..0..1..1. .1..1..1..0. .0..0..1..1. .1..0..0..1. .1..0..1..0
..0..1..0..0. .0..0..0..0. .0..1..0..0. .1..1..0..1. .0..1..1..0
CROSSREFS
Column 1 is A000045(n-1).
Column 2 is A231950(n-1).
Sequence in context: A298280 A299142 A299373 * A299067 A299728 A299839
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Feb 22 2018
STATUS
approved