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A316205
Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 3, 5 or 8 king-move adjacent elements, with upper left element zero.
1
8, 65, 271, 1253, 5925, 28597, 139490, 684312, 3366213, 16584659, 81780513, 403464509, 1991036145, 9826930119, 48505671446, 239434696258, 1181932661789, 5834512261471, 28801812411576, 142179503347321, 701867665502486
OFFSET
1,1
COMMENTS
Column 4 of A316209.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) +a(n-2) -26*a(n-3) -36*a(n-4) +34*a(n-5) +115*a(n-6) +8*a(n-7) +116*a(n-8) +479*a(n-9) +470*a(n-10) -921*a(n-11) -2129*a(n-12) -2526*a(n-13) -1334*a(n-14) -2284*a(n-15) -9146*a(n-16) -6996*a(n-17) +12466*a(n-18) +49749*a(n-19) +62187*a(n-20) +58207*a(n-21) +38318*a(n-22) +31677*a(n-23) -7533*a(n-24) -185254*a(n-25) -419983*a(n-26) -576029*a(n-27) -445146*a(n-28) -168343*a(n-29) +262995*a(n-30) +743110*a(n-31) +1100764*a(n-32) +1036585*a(n-33) +783312*a(n-34) +404555*a(n-35) -275418*a(n-36) -846744*a(n-37) -1061148*a(n-38) -799549*a(n-39) -452194*a(n-40) -67594*a(n-41) +110135*a(n-42) +190015*a(n-43) +173424*a(n-44) +110672*a(n-45) +27748*a(n-46) -22128*a(n-47) -41058*a(n-48) -42062*a(n-49) -15677*a(n-50) -2379*a(n-51) -3032*a(n-52) -2038*a(n-53) +3500*a(n-54) +3924*a(n-55) +1872*a(n-56) +432*a(n-57) for n>59
EXAMPLE
Some solutions for n=5
..0..0..0..1. .0..0..1..0. .0..1..0..0. .0..0..0..0. .0..1..1..0
..0..0..0..1. .1..0..0..0. .0..0..0..0. .0..0..0..0. .1..1..0..0
..1..1..1..1. .0..0..0..0. .0..0..0..1. .0..0..0..0. .0..0..0..0
..0..1..0..1. .1..1..0..0. .0..0..1..1. .1..1..0..0. .0..0..0..0
..0..0..0..0. .0..1..1..0. .1..0..1..0. .1..1..0..1. .1..0..0..1
CROSSREFS
Cf. A316209.
Sequence in context: A307436 A067685 A304306 * A305772 A317121 A009373
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 26 2018
STATUS
approved