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A297752
Number of 4Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 3 or 4 neighboring 1s.
1
1, 24, 230, 852, 3780, 28540, 187564, 1003470, 5652212, 35138340, 212926852, 1237635874, 7275468358, 43582711216, 259742505976, 1535394584256, 9097251626562, 54097987358160, 321364448756760, 1905998980152644
OFFSET
1,2
COMMENTS
Row 4 of A297749.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +6*a(n-2) +43*a(n-3) +361*a(n-4) -537*a(n-5) -2520*a(n-6) -7017*a(n-7) -34427*a(n-8) +24095*a(n-9) +219363*a(n-10) +292549*a(n-11) +551220*a(n-12) -580605*a(n-13) -3249682*a(n-14) -3068394*a(n-15) -5043685*a(n-16) +2287346*a(n-17) +17458278*a(n-18) +18065038*a(n-19) +28561403*a(n-20) +1147779*a(n-21) -30588887*a(n-22) -68279046*a(n-23) -58708191*a(n-24) -32747249*a(n-25) -48605698*a(n-26) +94893540*a(n-27) -23437785*a(n-28) +248514180*a(n-29) -3294356*a(n-30) +301663633*a(n-31) -247156554*a(n-32) +156249809*a(n-33) -376704483*a(n-34) +10728452*a(n-35) -288276582*a(n-36) +52825565*a(n-37) -70812797*a(n-38) +148150686*a(n-39) +26568786*a(n-40) +40239938*a(n-41) -34354481*a(n-42) +5164336*a(n-43) -20755892*a(n-44) +16194834*a(n-45) -5546935*a(n-46) +774526*a(n-47) +405718*a(n-48) -81154*a(n-49) -128862*a(n-50) +29288*a(n-51) -96*a(n-52)
EXAMPLE
Some solutions for n=7
..0..0..0..0..0..0..0. .0..0..0..1..1..1..0. .0..0..0..0..0..0..1
..0..1..0..1..1..1..1. .1..1..0..1..0..0..0. .0..0..1..0..0..1..1
..0..0..1..1..1..0..1. .0..0..0..1..0..0..1. .0..0..1..1..0..0..1
..0..0..0..0..1..0..0. .1..1..0..1..1..1..1. .0..0..0..0..1..0..0
CROSSREFS
Cf. A297749.
Sequence in context: A201192 A345648 A022684 * A027275 A027260 A125387
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 05 2018
STATUS
approved