login
A295712
Number of nX4 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 1, 2 or 4 1s.
1
16, 209, 2580, 31985, 396571, 4919857, 61023234, 756896741, 9388238587, 116447643403, 1444365516375, 17915279112880, 222213300241406, 2756236737260571, 34187156860885595, 424042564599435284
OFFSET
1,1
COMMENTS
Column 4 of A295716.
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) +29*a(n-2) +146*a(n-3) +207*a(n-4) +226*a(n-5) -429*a(n-6) -36*a(n-7) -458*a(n-8) -1628*a(n-9) -786*a(n-10) +346*a(n-11) +70*a(n-12) +39*a(n-13) +868*a(n-14) +670*a(n-15) -18*a(n-16) -347*a(n-17) -146*a(n-18) +a(n-19) +34*a(n-20) +22*a(n-21) +11*a(n-22) -23*a(n-23) -16*a(n-24) +6*a(n-25) +7*a(n-26) -a(n-28)
EXAMPLE
Some solutions for n=4
..0..1..0..1. .1..1..0..1. .1..1..1..1. .1..0..1..1. .0..1..1..0
..0..0..0..1. .1..0..0..0. .1..0..0..0. .0..0..1..0. .1..1..0..1
..0..0..0..1. .1..0..0..1. .1..0..1..0. .1..1..1..1. .0..0..0..0
..1..1..0..1. .0..1..1..1. .1..1..0..0. .0..0..1..1. .1..1..0..0
CROSSREFS
Cf. A295716.
Sequence in context: A285167 A283694 A283126 * A319236 A222447 A059385
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 26 2017
STATUS
approved