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A301839
Number of nX6 0..1 arrays with every element equal to 0, 1 or 2 horizontally or antidiagonally adjacent elements, with upper left element zero.
1
32, 855, 15199, 281758, 5240684, 97439921, 1812097252, 33701001773, 626769301255, 11656674265408, 216791623977204, 4031908496993218, 74985787605598453, 1394592394913802694, 25936755278154522723
OFFSET
1,1
COMMENTS
Column 6 of A301841.
LINKS
FORMULA
Empirical: a(n) = 45*a(n-1) -812*a(n-2) +8427*a(n-3) -59225*a(n-4) +308634*a(n-5) -1256189*a(n-6) +4115169*a(n-7) -11046335*a(n-8) +24584435*a(n-9) -45781016*a(n-10) +71898912*a(n-11) -95852394*a(n-12) +108964324*a(n-13) -105845027*a(n-14) +87815455*a(n-15) -62033967*a(n-16) +37077135*a(n-17) -18559186*a(n-18) +7664773*a(n-19) -2558244*a(n-20) +670720*a(n-21) -132612*a(n-22) +18528*a(n-23) -1616*a(n-24) +64*a(n-25) for n>27
EXAMPLE
Some solutions for n=5
..0..1..1..0..1..0. .0..0..1..0..0..1. .0..1..1..0..0..1. .0..0..1..0..1..1
..0..0..1..0..0..1. .0..1..0..1..0..0. .0..0..1..0..0..1. .0..1..1..0..1..0
..0..0..1..1..0..1. .0..1..1..0..1..1. .0..0..1..0..0..1. .0..1..0..0..1..0
..0..0..1..0..1..0. .0..0..1..0..0..1. .0..0..1..0..0..1. .0..1..1..0..1..0
..0..1..1..1..0..0. .0..1..1..0..1..0. .0..0..1..1..0..0. .0..0..1..0..1..0
CROSSREFS
Cf. A301841.
Sequence in context: A231161 A220460 A203957 * A302067 A281474 A302627
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 27 2018
STATUS
approved