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A317771
Number of nX6 0..1 arrays with every element unequal to 0, 1 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
13, 18, 28, 23, 30, 40, 54, 82, 115, 185, 266, 425, 649, 1028, 1588, 2487, 3908, 6096, 9677, 15103, 24079, 37679, 60164, 94986, 151370, 239771, 381764, 606952, 964659, 1536894, 2444020, 3894964, 6192473, 9874576, 15717153, 25054872, 39906589
OFFSET
1,1
COMMENTS
Column 6 of A317773.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-4) +4*a(n-7) -5*a(n-8) -a(n-9) +3*a(n-10) +17*a(n-11) -15*a(n-12) +17*a(n-13) -9*a(n-14) -41*a(n-15) -27*a(n-16) +39*a(n-17) -45*a(n-18) +2*a(n-19) +22*a(n-20) -22*a(n-21) -217*a(n-22) +33*a(n-23) +18*a(n-24) -36*a(n-25) +89*a(n-26) +298*a(n-27) -168*a(n-28) -194*a(n-29) -49*a(n-30) -67*a(n-31) -406*a(n-32) +156*a(n-33) +345*a(n-34) +144*a(n-35) +23*a(n-36) +211*a(n-37) -198*a(n-38) -383*a(n-39) -77*a(n-40) +135*a(n-41) +24*a(n-42) +122*a(n-43) +171*a(n-44) +58*a(n-45) -41*a(n-46) -24*a(n-47) +35*a(n-48) +58*a(n-49) +40*a(n-50) -8*a(n-51) -23*a(n-52) -51*a(n-53) -46*a(n-54) -16*a(n-55) +2*a(n-56) +12*a(n-57) +9*a(n-58) -6*a(n-59) -8*a(n-60) -2*a(n-61) -4*a(n-62) +3*a(n-64) +a(n-65) for n>72
EXAMPLE
Some solutions for n=5
..0..0..0..0..0..0. .0..0..1..1..1..1. .0..0..0..1..1..1. .0..0..0..1..1..1
..0..0..0..0..0..0. .0..0..0..1..1..1. .0..0..0..0..1..1. .0..0..0..0..1..1
..0..0..0..0..0..0. .0..0..0..0..1..1. .0..0..0..0..0..1. .0..0..0..0..0..1
..1..0..0..0..0..0. .1..0..0..0..0..1. .0..0..0..0..0..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. .1..0..0..0..0..0
CROSSREFS
Cf. A317773.
Sequence in context: A257373 A346561 A131019 * A037158 A318080 A066469
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 06 2018
STATUS
approved