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.

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

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences: A305582 A305583 A305584 * A305586 A305587 A305588

Keyword

nonn

Author

R. H. Hardin, Jun 05 2018

Status

approved