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A318032
Number of nX3 0..1 arrays with every element unequal to 0, 1, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
3, 6, 9, 25, 58, 152, 368, 904, 2211, 5420, 13257, 32485, 79687, 195459, 479166, 1174486, 2879048, 7057869, 17302114, 42416167, 103983959, 254916060, 624918591, 1531968302, 3755586548, 9206752113, 22570177681, 55330344496, 135641228111
OFFSET
1,1
COMMENTS
Column 3 of A318037.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -9*a(n-2) +7*a(n-3) +6*a(n-4) -27*a(n-5) +37*a(n-6) -22*a(n-7) -23*a(n-8) +31*a(n-9) +9*a(n-10) -29*a(n-11) +48*a(n-12) -27*a(n-13) +25*a(n-14) -8*a(n-15) -24*a(n-16) +28*a(n-17) -60*a(n-18) +60*a(n-19) -63*a(n-20) +49*a(n-21) -39*a(n-22) +25*a(n-23) -13*a(n-24) +4*a(n-25) +2*a(n-26) -3*a(n-27) +4*a(n-28) -a(n-29) +a(n-30) for n>33
EXAMPLE
Some solutions for n=5
..0..0..0. .0..0..0. .0..1..1. .0..0..0. .0..1..0. .0..0..0. .0..0..0
..0..0..1. .1..0..1. .0..0..1. .0..0..0. .0..1..1. .0..0..0. .1..0..0
..0..0..0. .0..1..0. .0..0..0. .1..0..0. .1..0..0. .0..0..0. .0..0..0
..0..0..0. .1..0..1. .0..0..0. .0..0..1. .0..1..1. .0..0..1. .0..0..0
..0..1..0. .0..0..0. .0..1..0. .0..0..0. .1..1..1. .0..0..0. .1..0..0
CROSSREFS
Cf. A318037.
Sequence in context: A026095 A061929 A358403 * A326160 A301536 A296110
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 13 2018
STATUS
approved