A305343 Number of nX4 0..1 arrays with every element unequal to 0, 1, 3, 5 or 8 king-move adjacent elements, with upper left element zero.

5, 21, 28, 77, 199, 454, 1074, 2619, 6216, 14782, 35494, 84850, 202493, 484472, 1158594, 2768565, 6619260, 15826963, 37833884, 90447825, 216242881, 516964232, 1235890365, 2954669861, 7063719452, 16887142919, 40372113631, 96517561505

Offset

1,1

Comments

Column 4 of A305347.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +4*a(n-3) -3*a(n-4) -4*a(n-5) +7*a(n-6) -8*a(n-7) +a(n-8) -21*a(n-9) +5*a(n-10) +10*a(n-11) -7*a(n-12) +8*a(n-13) -3*a(n-14) +34*a(n-15) +7*a(n-16) +2*a(n-17) -a(n-18) +5*a(n-20) -16*a(n-21) -12*a(n-22) -17*a(n-23) -3*a(n-25) -4*a(n-26) -4*a(n-27) +a(n-28) +10*a(n-29) +3*a(n-30) +a(n-31) +a(n-32) +3*a(n-33) +2*a(n-34) -a(n-35) -a(n-36) for n>37

Example

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

Crossrefs

Cf. A305347.

Sequence in context: A304351 A305914 A303036 * A186304 A316235 A317156

Adjacent sequences: A305340 A305341 A305342 * A305344 A305345 A305346

Keyword

nonn

Author

R. H. Hardin, May 30 2018

Status

approved