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

Author

R. H. Hardin, Mar 28 2018

Keywords

• nonn

Comments

Column 7 of A301906.

Examples

			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
		

Links

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

Crossrefs

Cf. A301906.

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) [phone]*a(n-15) -15194193*a(n-16) -250412*a(n-17) [phone]*a(n-18) -27506576*a(n-19) +1889508*a(n-20) [phone]*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