A317372 Number of nX4 0..1 arrays with every element unequal to 1, 2, 3, 4, 6, 7 or 8 king-move adjacent elements, with upper left element zero.

2, 86, 529, 4811, 42512, 360940, 3113246, 26916032, 231704568, 1997823756, 17226263836, 148491065088, 1280151235952, 11036257474349, 95142240617696, 820217339795577, 7071057070996869, 60959178690213291, 525525965321704727

Offset

1,1

Comments

Column 4 of A317376.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) +21*a(n-2) +53*a(n-3) -257*a(n-4) -758*a(n-5) +395*a(n-6) +497*a(n-7) +1981*a(n-8) +4397*a(n-9) +6537*a(n-10) +11095*a(n-11) +994*a(n-12) +88209*a(n-13) -45457*a(n-14) -176327*a(n-15) -283227*a(n-16) -613439*a(n-17) -282844*a(n-18) -1464941*a(n-19) +1360540*a(n-20) -992020*a(n-21) +4235214*a(n-22) -1280680*a(n-23) +10886486*a(n-24) +746991*a(n-25) -11257136*a(n-26) +17416848*a(n-27) -38758434*a(n-28) +57991863*a(n-29) -84864396*a(n-30) +76820034*a(n-31) -24490696*a(n-32) -6600419*a(n-33) -3202247*a(n-34) +18456186*a(n-35) -19751439*a(n-36) +2435516*a(n-37) +381098*a(n-38) +2798783*a(n-39) -215506*a(n-40) -103936*a(n-41) -218835*a(n-42) +172509*a(n-43) -7504*a(n-44) -94212*a(n-45) +24344*a(n-46) +2839*a(n-47) -1841*a(n-48) +626*a(n-49) +122*a(n-50) for n>51

Example

Some solutions for n=5
..0..0..1..0. .0..1..0..0. .0..1..1..0. .0..0..1..1. .0..1..0..1
..1..1..1..1. .1..0..1..0. .0..0..0..1. .0..1..0..0. .1..1..0..0
..0..1..1..1. .0..0..1..0. .0..0..0..0. .0..0..0..0. .0..1..1..1
..1..0..1..0. .1..0..0..1. .0..1..0..0. .1..0..1..1. .1..0..1..1
..0..0..0..1. .0..1..1..0. .1..1..0..1. .1..0..0..1. .1..1..0..0

Crossrefs

Cf. A317376.

Sequence in context: A304593 A316379 A306139 * A358807 A177318 A280551

Adjacent sequences: A317369 A317370 A317371 * A317373 A317374 A317375

Keyword

nonn

Author

R. H. Hardin, Jul 26 2018

Status

approved