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A282965
Number of nX4 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements.
1
1, 17, 309, 3635, 35870, 346172, 3128641, 27439857, 234322382, 1959091067, 16107499923, 130573017760, 1045978247546, 8294049221347, 65189007190923, 508421219807214, 3938274043202322, 30321280493011911, 232179051504428919
OFFSET
1,2
COMMENTS
Column 4 of A282969.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +69*a(n-2) +115*a(n-3) -1662*a(n-4) -10569*a(n-5) -20610*a(n-6) +66408*a(n-7) +672108*a(n-8) +3005903*a(n-9) +9699504*a(n-10) +25213452*a(n-11) +55333514*a(n-12) +105107715*a(n-13) +175123596*a(n-14) +257872978*a(n-15) +336770919*a(n-16) +389418987*a(n-17) +396223120*a(n-18) +351286416*a(n-19) +263211645*a(n-20) +157198801*a(n-21) +63543780*a(n-22) -3391824*a(n-23) -38331570*a(n-24) -27733227*a(n-25) -47295936*a(n-26) -11161884*a(n-27) -8536407*a(n-28) -37322961*a(n-29) -6115148*a(n-30) +99311175*a(n-31) -314225052*a(n-32) +592510471*a(n-33) -825836292*a(n-34) +894811362*a(n-35) -728073601*a(n-36) +400560960*a(n-37) -74765559*a(n-38) -114713685*a(n-39) +150711576*a(n-40) -101336997*a(n-41) +42783221*a(n-42) -7302666*a(n-43) -7258503*a(n-44) +9597844*a(n-45) -6100839*a(n-46) +1992408*a(n-47) +21769*a(n-48) -393780*a(n-49) +293190*a(n-50) -161963*a(n-51) +49620*a(n-52) +8322*a(n-53) -14059*a(n-54) +5469*a(n-55) -1329*a(n-56) +312*a(n-57) +123*a(n-58) -183*a(n-59) +61*a(n-60) +3*a(n-61) -6*a(n-62) +a(n-63)
EXAMPLE
Some solutions for n=4
..1..0..0..0. .1..0..1..0. .1..0..1..0. .1..1..1..1. .1..0..0..0
..0..1..0..1. .0..0..0..1. .1..0..1..1. .0..0..0..0. .0..1..1..0
..0..1..1..0. .1..0..0..1. .0..1..0..0. .1..0..0..0. .0..0..0..0
..0..0..0..0. .1..1..0..1. .1..0..0..1. .0..0..1..0. .1..1..1..1
CROSSREFS
Cf. A282969.
Sequence in context: A156085 A129992 A197526 * A142428 A331492 A244764
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 25 2017
STATUS
approved