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A306056
Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 4, 6 or 7 king-move adjacent elements, with upper left element zero.
1
8, 24, 58, 164, 608, 2168, 6955, 23269, 80463, 271633, 908820, 3081846, 10454616, 35254223, 119067103, 402989356, 1362262739, 4602409803, 15559718166, 52607165051, 177810355067, 601025502460, 2031788683772, 6868166849601
OFFSET
1,1
COMMENTS
Column 4 of A306060.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +5*a(n-2) +13*a(n-3) -18*a(n-4) -89*a(n-5) -128*a(n-6) +135*a(n-7) +493*a(n-8) +299*a(n-9) -209*a(n-10) -24*a(n-11) +362*a(n-12) -2155*a(n-13) -3834*a(n-14) -20*a(n-15) +4446*a(n-16) +447*a(n-17) -4681*a(n-18) +10479*a(n-19) +16850*a(n-20) -10382*a(n-21) -28235*a(n-22) +8017*a(n-23) +47458*a(n-24) +19384*a(n-25) -11534*a(n-26) -30990*a(n-27) -62737*a(n-28) -63327*a(n-29) +15179*a(n-30) +24242*a(n-31) -26770*a(n-32) +2940*a(n-33) +47267*a(n-34) -3255*a(n-35) +21490*a(n-36) +114037*a(n-37) +70641*a(n-38) -19587*a(n-39) +15165*a(n-40) +20125*a(n-41) -72696*a(n-42) -77392*a(n-43) -14993*a(n-44) -18504*a(n-45) -32140*a(n-46) +17133*a(n-47) +37141*a(n-48) +7270*a(n-49) -10861*a(n-50) -3813*a(n-51) +816*a(n-52) +3906*a(n-53) +5575*a(n-54) +1654*a(n-55) -1038*a(n-56) -57*a(n-57) +494*a(n-58) -777*a(n-59) -792*a(n-60) -190*a(n-61) +18*a(n-62) +4*a(n-63) +52*a(n-64) +48*a(n-65) for n>67
EXAMPLE
Some solutions for n=5
..0..0..1..1. .0..0..0..0. .0..0..0..0. .0..0..0..0. .0..1..1..0
..0..0..0..0. .0..0..0..0. .1..0..0..0. .0..1..1..0. .0..1..1..0
..0..0..0..0. .0..0..1..0. .0..1..0..0. .1..0..0..0. .1..1..1..1
..0..0..1..0. .0..0..0..1. .1..1..1..1. .1..1..1..0. .1..1..1..1
..0..0..1..0. .0..0..0..0. .1..1..1..1. .1..0..0..0. .0..0..1..1
CROSSREFS
Cf. A306060.
Sequence in context: A159741 A302489 A099041 * A129959 A256533 A177719
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 18 2018
STATUS
approved