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A297872
Number of nX4 0..1 arrays with every element equal to 2, 3 or 5 king-move adjacent elements, with upper left element zero.
1
0, 2, 3, 10, 20, 68, 185, 561, 1588, 4814, 14322, 42658, 127606, 381695, 1142358, 3419569, 10243325, 30685488, 91937645, 275496007, 825602377, 2474298468, 7415685876, 22226227933, 66617647655, 199673303891, 598488700247
OFFSET
1,2
COMMENTS
Column 4 of A297876.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -5*a(n-2) -2*a(n-3) -5*a(n-4) +3*a(n-5) +36*a(n-7) -57*a(n-8) +81*a(n-9) +32*a(n-10) -6*a(n-11) -102*a(n-12) -12*a(n-13) -182*a(n-14) -286*a(n-15) +443*a(n-16) -410*a(n-17) +222*a(n-18) -755*a(n-19) +2597*a(n-20) -997*a(n-21) +788*a(n-22) -95*a(n-23) +2600*a(n-24) -2288*a(n-25) -2866*a(n-26) -1124*a(n-27) +2189*a(n-28) -1950*a(n-29) -3437*a(n-30) +2422*a(n-31) +115*a(n-32) +1748*a(n-33) +1283*a(n-34) +1645*a(n-35) +38*a(n-36) +415*a(n-37) -862*a(n-38) +338*a(n-39) -437*a(n-40) -1030*a(n-41) -286*a(n-42) -150*a(n-43) +337*a(n-44) -83*a(n-45) +41*a(n-46) -33*a(n-47) +71*a(n-48) +14*a(n-49) +8*a(n-50) -6*a(n-51) -4*a(n-52) for n>53
EXAMPLE
Some solutions for n=7
..0..0..1..1. .0..0..1..1. .0..0..1..1. .0..0..1..1. .0..0..1..1
..1..0..1..0. .1..0..1..0. .0..1..0..1. .0..1..0..1. .0..1..1..0
..1..1..0..0. .1..1..0..0. .0..1..0..1. .1..0..1..0. .1..0..0..0
..1..0..1..0. .1..0..1..0. .1..0..0..1. .1..0..1..0. .1..0..1..0
..0..0..1..1. .0..0..1..0. .0..1..0..1. .1..1..0..1. .0..1..1..0
..1..0..1..0. .1..0..1..0. .0..1..0..1. .0..1..1..0. .1..0..1..0
..1..1..0..0. .1..1..0..0. .0..0..1..1. .0..0..0..0. .1..1..0..0
CROSSREFS
Cf. A297876.
Sequence in context: A148054 A148055 A089791 * A298135 A226356 A141050
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 07 2018
STATUS
approved