A301905 Number of nX7 0..1 arrays with every element equal to 0, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.

1, 10, 12, 96, 320, 1934, 8781, 49709, 253844, 1413100, 7620270, 42580016, 235818861, 1324997099, 7432214130, 41943560072, 236751899580, 1339917222874, 7587029374109, 43012592771281, 243943851904936, 1384324886282580

Offset

1,2

Comments

Column 7 of A301906.

Links

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

Formula

Empirical: a(n) = 19*a(n-1) -129*a(n-2) +266*a(n-3) +1113*a(n-4) -7787*a(n-5) +16342*a(n-6) +7083*a(n-7) -129016*a(n-8) +332445*a(n-9) -231596*a(n-10) -894953*a(n-11) +2912737*a(n-12) -3222398*a(n-13) -2103447*a(n-14) +12042025*a(n-15) -15194193*a(n-16) -250412*a(n-17) +24253854*a(n-18) -27506576*a(n-19) +1889508*a(n-20) +22587616*a(n-21) -20220872*a(n-22) +2087728*a(n-23) +8489920*a(n-24) -6518528*a(n-25) +1174848*a(n-26) +1096960*a(n-27) -792192*a(n-28) +188672*a(n-29) -9216*a(n-30) for n>33

Example

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

Crossrefs

Cf. A301906.

Sequence in context: A370976 A241252 A336892 * A167321 A258484 A116118

Adjacent sequences: A301902 A301903 A301904 * A301906 A301907 A301908

Keyword

nonn

Author

R. H. Hardin, Mar 28 2018

Status

approved