A283228 Number of nX4 0..1 arrays with no 1 equal to more than two of its horizontal and vertical neighbors, with the exception of exactly two elements.

0, 6, 395, 8592, 163860, 2875836, 47531178, 753320466, 11573758019, 173540942990, 2551737823936, 36922336262476, 527103036641574, 7439264341235380, 103963898544212173, 1440480444975841286, 19808724383714310896

Offset

1,2

Comments

Column 4 of A283232.

Links

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

Formula

Empirical: a(n) = 27*a(n-1) -165*a(n-2) -234*a(n-3) -3129*a(n-4) +22416*a(n-5) +159152*a(n-6) +1030014*a(n-7) +3401490*a(n-8) +9668304*a(n-9) +14625564*a(n-10) +12014199*a(n-11) -37229470*a(n-12) -103402119*a(n-13) -171763266*a(n-14) +8354570*a(n-15) +254906391*a(n-16) +384743559*a(n-17) -123324128*a(n-18) -421598184*a(n-19) +628179321*a(n-20) +221724497*a(n-21) -1083423084*a(n-22) +249815562*a(n-23) +858637588*a(n-24) -920514603*a(n-25) -506962308*a(n-26) +883018391*a(n-27) -119359263*a(n-28) -648783024*a(n-29) +364210256*a(n-30) +278523843*a(n-31) -341026164*a(n-32) -28626721*a(n-33) +212356545*a(n-34) -50258766*a(n-35) -85509859*a(n-36) +52041366*a(n-37) +22638720*a(n-38) -29260115*a(n-39) -2214948*a(n-40) +11531682*a(n-41) -1415738*a(n-42) -3657156*a(n-43) +711432*a(n-44) +897796*a(n-45) -137640*a(n-46) -146136*a(n-47) +12088*a(n-48) +13344*a(n-49) -384*a(n-50) -512*a(n-51)

Example

Some solutions for n=4
..1..1..0..1. .1..1..1..1. .1..1..1..0. .1..1..1..1. .0..1..1..1
..1..1..1..0. .0..0..1..1. .1..0..1..0. .0..1..1..0. .1..0..1..0
..1..0..1..0. .0..1..1..0. .1..1..1..1. .1..0..0..0. .1..1..0..0
..1..1..1..0. .1..0..0..0. .1..0..1..0. .0..1..1..1. .1..0..1..1

Crossrefs

Cf. A283232.

Sequence in context: A162137 A119645 A338115 * A278322 A229599 A290324

Adjacent sequences: A283225 A283226 A283227 * A283229 A283230 A283231

Keyword

nonn

Author

R. H. Hardin, Mar 03 2017

Status

approved