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A317899
Number of nX5 0..1 arrays with every element unequal to 2, 3 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
0, 4, 2, 31, 29, 75, 315, 708, 1978, 4962, 13865, 38184, 101161, 277625, 735028, 2021158, 5400624, 14720342, 39564863, 107260441, 289679573, 782878461, 2118368915, 5719199275, 15480779502, 41801779217, 113104257456, 305561736347
OFFSET
1,2
COMMENTS
Column 5 of A317902.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-2) +5*a(n-3) +17*a(n-4) +30*a(n-5) -7*a(n-6) -26*a(n-7) -207*a(n-8) -310*a(n-9) -699*a(n-10) -320*a(n-11) -532*a(n-12) +1394*a(n-13) +1961*a(n-14) +6075*a(n-15) +5948*a(n-16) +8985*a(n-17) +5504*a(n-18) +1495*a(n-19) -7953*a(n-20) -21568*a(n-21) -29828*a(n-22) -50141*a(n-23) -47334*a(n-24) -61895*a(n-25) -42016*a(n-26) -39584*a(n-27) -5937*a(n-28) +26020*a(n-29) +58551*a(n-30) +109421*a(n-31) +121801*a(n-32) +152120*a(n-33) +118649*a(n-34) +99846*a(n-35) +33711*a(n-36) -17288*a(n-37) -67755*a(n-38) -93548*a(n-39) -95925*a(n-40) -73856*a(n-41) -47065*a(n-42) -29812*a(n-43) -14578*a(n-44) -5442*a(n-45) +5951*a(n-46) -1155*a(n-47) +2068*a(n-48) +7921*a(n-49) +808*a(n-50) -113*a(n-51) +2959*a(n-52) +374*a(n-53) -811*a(n-54) +701*a(n-55) +216*a(n-56) -174*a(n-57) +22*a(n-58) +11*a(n-59) -6*a(n-60) +2*a(n-61) for n>69
EXAMPLE
Some solutions for n=5
..0..1..1..0..1. .0..1..1..0..1. .0..1..0..0..1. .0..1..0..0..0
..1..0..0..0..0. .1..0..0..0..1. .1..0..1..0..1. .1..1..1..1..1
..0..0..1..1..1. .0..0..1..0..0. .0..0..0..0..0. .0..1..1..0..0
..1..1..1..0..1. .1..0..0..0..1. .1..0..1..0..1. .0..0..0..0..1
..0..0..1..1..0. .1..0..1..1..0. .1..0..0..1..0. .1..0..1..1..0
CROSSREFS
Cf. A317902.
Sequence in context: A093991 A030447 A302369 * A076936 A344536 A348567
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 10 2018
STATUS
approved