login
A316423
Number of nX4 0..1 arrays with every element unequal to 0, 1, 3, 5, 6 or 8 king-move adjacent elements, with upper left element zero.
1
5, 21, 32, 97, 279, 640, 1660, 4353, 10975, 28038, 72143, 184345, 471036, 1206844, 3088559, 7899309, 20219520, 51748319, 132403281, 338838244, 867145134, 2218951631, 5678392645, 14531503004, 37186210193, 95160712029, 243521427174
OFFSET
1,1
COMMENTS
Column 4 of A316427.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +16*a(n-3) -24*a(n-4) -4*a(n-5) -97*a(n-6) +111*a(n-7) +33*a(n-8) +301*a(n-9) -280*a(n-10) -102*a(n-11) -610*a(n-12) +462*a(n-13) +137*a(n-14) +1003*a(n-15) -460*a(n-16) -49*a(n-17) -1229*a(n-18) +318*a(n-19) -40*a(n-20) +1076*a(n-21) -170*a(n-22) +59*a(n-23) -756*a(n-24) -85*a(n-25) -26*a(n-26) +258*a(n-27) -2*a(n-28) -278*a(n-29) -208*a(n-30) -158*a(n-31) +113*a(n-32) -92*a(n-33) +85*a(n-34) +71*a(n-35) +166*a(n-36) +46*a(n-37) -49*a(n-38) -63*a(n-39) -10*a(n-40) +6*a(n-41) +6*a(n-42) for n>43
EXAMPLE
Some solutions for n=5
..0..0..0..0. .0..0..0..1. .0..1..0..0. .0..0..1..1. .0..1..1..1
..1..0..0..0. .0..0..0..0. .1..1..0..1. .0..0..0..1. .1..1..1..1
..0..0..0..0. .0..0..0..0. .1..1..1..1. .1..0..1..1. .1..1..1..1
..0..0..0..0. .0..0..1..0. .1..1..1..1. .1..1..1..1. .0..1..1..0
..0..0..0..0. .0..0..0..0. .0..1..1..0. .1..1..1..1. .1..1..1..1
CROSSREFS
Cf. A316427.
Sequence in context: A306168 A305645 A316921 * A317425 A074074 A006309
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 02 2018
STATUS
approved