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A305585
Number of nX7 0..1 arrays with every element unequal to 0, 1, 2, 7 or 8 king-move adjacent elements, with upper left element zero.
1
64, 21, 60, 247, 967, 8182, 50618, 280791, 1818586, 11395966, 69071165, 429700390, 2669916361, 16466195743, 101931570819, 631415640507, 3905674290991, 24169145746901, 149603254059227, 925791872791077, 5729240389493687
OFFSET
1,1
COMMENTS
Column 7 of A305586.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +12*a(n-2) +110*a(n-3) +4*a(n-4) -452*a(n-5) -3169*a(n-6) -798*a(n-7) +5057*a(n-8) +37850*a(n-9) +11291*a(n-10) -28056*a(n-11) -261721*a(n-12) -49891*a(n-13) +84479*a(n-14) +1181096*a(n-15) +103279*a(n-16) -89436*a(n-17) -3704935*a(n-18) -77047*a(n-19) -567614*a(n-20) +8224574*a(n-21) +15957*a(n-22) +2297906*a(n-23) -12515617*a(n-24) +16774*a(n-25) -4217736*a(n-26) +13481088*a(n-27) -228618*a(n-28) +4384142*a(n-29) -10432900*a(n-30) +252264*a(n-31) -2810970*a(n-32) +5945668*a(n-33) -88068*a(n-34) +1287984*a(n-35) -2419648*a(n-36) -71164*a(n-37) -407840*a(n-38) +592696*a(n-39) +67728*a(n-40) +61920*a(n-41) -70128*a(n-42) -8064*a(n-43) -3456*a(n-44) +5184*a(n-45) for n>50
EXAMPLE
Some solutions for n=5
..0..0..0..0..0..0..1. .0..0..0..0..0..0..0. .0..0..0..0..0..0..0
..0..0..1..0..0..1..0. .0..1..0..0..0..0..0. .0..0..0..0..0..1..0
..0..0..0..0..0..0..0. .0..0..1..0..0..1..0. .0..1..0..0..0..0..0
..0..0..0..0..1..0..0. .0..0..0..0..0..1..0. .0..1..0..0..0..1..0
..0..0..0..0..0..0..0. .0..0..0..0..0..0..0. .0..0..0..0..0..0..0
CROSSREFS
Cf. A305586.
Sequence in context: A147792 A304229 A305039 * A316692 A302217 A302465
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 05 2018
STATUS
approved