A275224 Number of nX4 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,0) and new values introduced in order 0..2.

14, 216, 339, 1302, 6448, 32388, 164645, 844176, 4319300, 22083548, 112975642, 578036947, 2957212295, 15128798774, 77399122215, 395975649916, 2025811842566, 10364054079218, 53022552043867, 271263640161978, 1387785882638203

Offset

1,1

Comments

Column 4 of A275228.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -4*a(n-2) +18*a(n-4) -213*a(n-5) +254*a(n-6) -43*a(n-7) +348*a(n-8) +571*a(n-9) -1746*a(n-10) -33*a(n-11) +741*a(n-12) -1412*a(n-13) +2606*a(n-14) -243*a(n-15) -667*a(n-16) +1424*a(n-17) -2763*a(n-18) +1382*a(n-19) -742*a(n-20) +329*a(n-21) +281*a(n-22) -97*a(n-23) +88*a(n-24) -62*a(n-25) -27*a(n-26) -3*a(n-27) +7*a(n-28) -a(n-29) +3*a(n-30) -a(n-31) for n>35

Example

Some solutions for n=4
..0..1..2..0. .0..1..2..0. .0..1..0..1. .0..0..0..0. .0..1..0..2
..1..2..0..1. .1..0..1..2. .1..0..1..0. .1..2..1..1. .1..0..2..0
..0..1..2..0. .0..1..2..0. .0..2..0..1. .2..1..2..2. .2..2..0..1
..1..2..0..1. .1..0..1..2. .2..0..1..0. .1..0..0..0. .1..0..1..0

Crossrefs

Cf. A275228.

Sequence in context: A202976 A331494 A208430 * A275144 A275354 A121972

Adjacent sequences: A275221 A275222 A275223 * A275225 A275226 A275227

Keyword

nonn

Author

R. H. Hardin, Jul 20 2016

Status

approved