A207342 Number of nX4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 0 and 1 1 1 vertically

9, 81, 192, 828, 3130, 11230, 43260, 163710, 604340, 2295512, 8644786, 32247604, 121846736, 458125776, 1716149678, 6468493030, 24309087961, 91233180855, 343432736925, 1290560157455, 4847684885645, 18235756500631, 68530310193276

Offset

1,1

Comments

Column 4 of A207346

Links

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

Formula

Empirical: a(n) = 2*a(n-2) +64*a(n-3) +19*a(n-4) -30*a(n-5) -1264*a(n-6) -412*a(n-7) +509*a(n-8) +11226*a(n-9) +4125*a(n-10) -7984*a(n-11) -48526*a(n-12) -21168*a(n-13) +56453*a(n-14) +90870*a(n-15) +44166*a(n-16) -165266*a(n-17) -604*a(n-18) +11976*a(n-19) +127602*a(n-20) -222084*a(n-21) -139349*a(n-22) +215646*a(n-23) +160783*a(n-24) +133104*a(n-25) -315422*a(n-26) +178506*a(n-27) -76744*a(n-28) +16220*a(n-29) -172129*a(n-30) +47480*a(n-31) +60151*a(n-32) -4410*a(n-33) +6681*a(n-34) +13948*a(n-35) +10141*a(n-36) -9158*a(n-37) -9200*a(n-38) +5102*a(n-39) -3391*a(n-40) -714*a(n-41) +245*a(n-42) +394*a(n-43) +36*a(n-44) +72*a(n-45) +73*a(n-46) +6*a(n-47) -a(n-48) for n>51

Example

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

Crossrefs

Sequence in context: A207886 A207731 A208690 * A207271 A207764 A207662

Adjacent sequences: A207339 A207340 A207341 * A207343 A207344 A207345

Keyword

nonn

Author

R. H. Hardin Feb 17 2012

Status

approved