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A298891
Number of nX4 0..1 arrays with every element equal to 2, 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.
1
0, 2, 4, 11, 31, 80, 229, 681, 1969, 5973, 18031, 54874, 167752, 513625, 1575095, 4835994, 14859480, 45674676, 140452387, 431987865, 1328865560, 4088283165, 12578581331, 38703117525, 119090222855, 366452309799, 1127630050984
OFFSET
1,2
COMMENTS
Column 4 of A298895.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -9*a(n-2) +5*a(n-3) -32*a(n-4) +38*a(n-5) +25*a(n-6) +98*a(n-7) -119*a(n-8) +40*a(n-9) -550*a(n-10) +580*a(n-11) -916*a(n-12) +830*a(n-13) +263*a(n-14) +83*a(n-15) +2328*a(n-16) -229*a(n-17) +503*a(n-18) -4047*a(n-19) -417*a(n-20) -3044*a(n-21) +2435*a(n-22) -11065*a(n-23) +3356*a(n-24) -5303*a(n-25) +1559*a(n-26) +14545*a(n-27) +32995*a(n-28) +22512*a(n-29) -15204*a(n-30) -12820*a(n-31) -31577*a(n-32) -21644*a(n-33) +3315*a(n-34) +18307*a(n-35) -24537*a(n-36) -14373*a(n-37) +11731*a(n-38) +26599*a(n-39) +15792*a(n-40) -11544*a(n-41) -3386*a(n-42) -4977*a(n-43) +5179*a(n-44) -2851*a(n-45) +4056*a(n-46) -977*a(n-47) +3855*a(n-48) -121*a(n-49) +305*a(n-50) -1567*a(n-51) -458*a(n-52) -273*a(n-53) +321*a(n-54) -8*a(n-55) +78*a(n-56) -20*a(n-57) -6*a(n-58) for n>59
EXAMPLE
Some solutions for n=7
..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..1
..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..1..1..0. .0..1..0..1
..0..0..0..0. .0..0..0..0. .0..0..0..0. .1..0..0..1. .1..0..0..1
..1..1..1..1. .1..1..1..1. .0..0..0..0. .1..1..1..1. .1..1..1..1
..1..0..0..1. .1..1..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. .0..0..0..0. .0..0..0..0
..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0
CROSSREFS
Cf. A298895.
Sequence in context: A193059 A034770 A276687 * A002387 A325922 A148160
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 28 2018
STATUS
approved