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A268637 Number of nX6 0..2 arrays with some element plus some horizontally or vertically adjacent neighbor totalling two exactly once. 1
240, 7128, 163878, 3440052, 68710116, 1328460312, 25093766490, 465757993812, 8527096170390, 154406753980596, 2770879234068744, 49351916066147196, 873425626212657504, 15373652306609086368, 269322517606253198046 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A268639.

LINKS

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

FORMULA

Empirical: a(n) = 60*a(n-1) -1482*a(n-2) +20016*a(n-3) -167163*a(n-4) +924894*a(n-5) -3537110*a(n-6) +9593166*a(n-7) -18693789*a(n-8) +26218062*a(n-9) -26188161*a(n-10) +18139608*a(n-11) -8262712*a(n-12) +2220864*a(n-13) -266256*a(n-14) for n>15

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Cf. A268639.

Sequence in context: A145094 A239245 A218131 * A264317 A270174 A008340

Adjacent sequences:  A268634 A268635 A268636 * A268638 A268639 A268640

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 09 2016

STATUS

approved

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Last modified September 28 22:34 EDT 2021. Contains 347717 sequences. (Running on oeis4.)