A268796 Number of nX6 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two exactly once.

240, 1714, 11948, 117062, 1158904, 11138352, 104971262, 974000420, 8927994302, 81031120788, 729449219322, 6521558348746, 57964319359808, 512593621373638, 4513059897036336, 39580897460175788, 345946165584055346

Offset

1,1

Comments

Column 6 of A268798.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

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..0..0..0..0..1. .2..1..1..2..2..2. .1..0..0..0..0..0. .0..1..0..1..0..0
..0..0..0..1..0..1. .2..2..2..2..2..2. .0..0..0..0..0..0. .0..0..0..0..1..0
..1..0..0..0..0..0. .2..2..2..2..2..2. .1..0..0..0..0..0. .0..0..1..0..0..0
..0..0..1..0..0..1. .2..2..2..2..2..1. .0..0..1..1..0..1. .1..0..1..0..1..0

Crossrefs

Cf. A268798.

Sequence in context: A157766 A268906 A234763 * A290655 A212781 A205264

Adjacent sequences: A268793 A268794 A268795 * A268797 A268798 A268799

Keyword

nonn

Author

R. H. Hardin, Feb 13 2016

Status

approved