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A268807
Number of nX6 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.
1
336, 1972, 14308, 135912, 1316226, 12432856, 115671422, 1062318610, 9657289546, 87052567448, 779167091050, 6932066063186, 61353778718298, 540579543332426, 4744132651089162, 41488807479780664, 361699301828001722
OFFSET
1,1
COMMENTS
Column 6 of A268809.
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) for n>45
EXAMPLE
Some solutions for n=4
..0..1..0..1..0..0. .1..2..2..2..1..2. .2..1..2..2..2..2. .0..0..1..0..0..1
..1..0..0..0..1..0. .1..2..2..2..2..1. .1..2..2..2..2..2. .0..0..1..0..0..0
..0..0..1..0..0..0. .2..2..2..2..2..2. .2..1..2..2..2..1. .1..0..0..0..0..0
..1..0..0..1..0..1. .2..2..2..2..2..1. .2..2..1..2..2..2. .0..1..0..1..0..0
CROSSREFS
Cf. A268809.
Sequence in context: A059467 A348343 A237862 * A159206 A251066 A269050
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 13 2016
STATUS
approved