A301969 Number of 7Xn 0..1 arrays with every element equal to 0, 1 or 4 horizontally or antidiagonally adjacent elements, with upper left element zero.

64, 610, 632, 1156, 2454, 8705, 33860, 120603, 444357, 1715911, 6574776, 25055403, 96049774, 368934080, 1415983660, 5435511772, 20873907896, 80167521480, 307889914336, 1182522157914, 4541861862000, 17444676630768, 67003068862917

Offset

1,1

Comments

Row 7 of A301964.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +31*a(n-3) +10*a(n-4) +30*a(n-5) -282*a(n-6) -548*a(n-7) -1110*a(n-8) -220*a(n-9) +2288*a(n-10) +7498*a(n-11) +11635*a(n-12) +8602*a(n-13) -7081*a(n-14) -33921*a(n-15) -52592*a(n-16) -42945*a(n-17) +4748*a(n-18) +65470*a(n-19) +93586*a(n-20) +61066*a(n-21) -17191*a(n-22) -82766*a(n-23) -86139*a(n-24) -28107*a(n-25) +39729*a(n-26) +63115*a(n-27) +34943*a(n-28) -9501*a(n-29) -29505*a(n-30) -17331*a(n-31) +4542*a(n-32) +13303*a(n-33) +6480*a(n-34) -2878*a(n-35) -5323*a(n-36) -2066*a(n-37) +1003*a(n-38) +1389*a(n-39) +444*a(n-40) -173*a(n-41) -193*a(n-42) -60*a(n-43) +5*a(n-44) +9*a(n-45) +4*a(n-46) +a(n-47) for n>52

Example

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

Crossrefs

Cf. A301964.

Sequence in context: A330831 A177757 A301796 * A208642 A301890 A302086

Adjacent sequences: A301966 A301967 A301968 * A301970 A301971 A301972

Keyword

nonn

Author

R. H. Hardin, Mar 29 2018

Status

approved