login
A268787
Number of nX6 binary arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two exactly once.
1
20, 338, 4207, 46195, 477128, 4725018, 45515227, 429442918, 3988796543, 36591758790, 332327545513, 2993282062865, 26773510121640, 238060527618025, 2105957538309226, 18547209960131466, 162707970808249851
OFFSET
1,1
COMMENTS
Column 6 of A268789.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +83*a(n-2) +210*a(n-3) -1918*a(n-4) -13444*a(n-5) -27431*a(n-6) +22868*a(n-7) +172414*a(n-8) +91292*a(n-9) -572846*a(n-10) -576908*a(n-11) +1569339*a(n-12) +1662464*a(n-13) -4129647*a(n-14) -2739590*a(n-15) +10005684*a(n-16) +128072*a(n-17) -18820309*a(n-18) +14239344*a(n-19) +18275195*a(n-20) -39512592*a(n-21) +16595129*a(n-22) +32600294*a(n-23) -63035320*a(n-24) +55225574*a(n-25) -27556538*a(n-26) +5959238*a(n-27) +1367780*a(n-28) -935764*a(n-29) -205936*a(n-30) +253428*a(n-31) -6946*a(n-32) -44268*a(n-33) +5192*a(n-34) +6896*a(n-35) -1085*a(n-36) -848*a(n-37) +74*a(n-38) +94*a(n-39) +3*a(n-40) -6*a(n-41) -a(n-42)
EXAMPLE
Some solutions for n=4
..0..0..0..0..1..0. .0..0..1..0..0..0. .0..1..0..0..0..0. .0..1..0..1..0..1
..1..0..0..1..0..0. .0..0..0..1..0..0. .0..0..1..0..1..0. .0..0..1..0..0..0
..0..1..0..0..0..1. .0..0..0..0..1..1. .0..0..0..1..0..0. .0..0..0..0..1..0
..0..0..1..0..0..0. .0..0..0..0..0..0. .0..0..0..0..1..0. .1..0..0..0..0..1
CROSSREFS
Cf. A268789.
Sequence in context: A084032 A166984 A167031 * A272183 A005748 A230236
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 13 2016
STATUS
approved