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A316692
Number of n X 7 0..1 arrays with every element unequal to 0, 1, 2, 6, 7 or 8 king-move adjacent elements, with upper left element zero.
1
64, 21, 81, 313, 1125, 9442, 61454, 342508, 2212378, 14109348, 86477928, 541484462, 3400774549, 21195268549, 132406833468, 828277255783, 5174739183171, 32333305874846, 202097767759162, 1262976862661335, 7892519184607337
OFFSET
1,1
COMMENTS
Column 7 of A316693.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +12*a(n-2) +110*a(n-3) +26*a(n-4) -415*a(n-5) -3065*a(n-6) -1514*a(n-7) +3667*a(n-8) +33884*a(n-9) +19541*a(n-10) -12055*a(n-11) -215062*a(n-12) -98825*a(n-13) +502*a(n-14) +882896*a(n-15) +306568*a(n-16) +150206*a(n-17) -2481993*a(n-18) -650282*a(n-19) -864282*a(n-20) +4763862*a(n-21) +1085395*a(n-22) +2069629*a(n-23) -5956995*a(n-24) -1394383*a(n-25) -2946869*a(n-26) +5150227*a(n-27) +1230622*a(n-28) +2722066*a(n-29) -3058411*a(n-30) -1045031*a(n-31) -1731070*a(n-32) +1264814*a(n-33) +738227*a(n-34) +812157*a(n-35) -315914*a(n-36) -356366*a(n-37) -245556*a(n-38) +10608*a(n-39) +98176*a(n-40) +36476*a(n-41) +7552*a(n-42) -8952*a(n-43) -1648*a(n-44) -256*a(n-45) +352*a(n-46) for n>52.
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..1..0..0..0..1..0. .0..0..1..0..0..0..0. .0..0..1..0..0..1..0
..0..0..1..0..0..0..0. .0..0..0..0..0..1..0. .0..0..0..0..0..0..0
..0..0..0..0..0..0..0. .0..0..0..1..0..0..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..0..0..0
CROSSREFS
Cf. A316693.
Sequence in context: A304229 A305039 A305585 * A302217 A302465 A303247
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 10 2018
STATUS
approved