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A303178
Number of nX4 0..1 arrays with every element equal to 0, 1, 2, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
8, 37, 72, 297, 1302, 5050, 20188, 81926, 329957, 1329466, 5358347, 21608578, 87101482, 351134917, 1415564660, 5706662796, 23005513674, 92743499633, 373882345405, 1507253219678, 6076276040079, 24495641982958, 98750689289605
OFFSET
1,1
COMMENTS
Column 4 of A303182.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +6*a(n-2) -a(n-3) -15*a(n-4) -47*a(n-5) -18*a(n-6) +91*a(n-7) +121*a(n-8) +35*a(n-9) -33*a(n-10) -205*a(n-11) -172*a(n-12) -49*a(n-13) +107*a(n-14) +182*a(n-15) -26*a(n-16) +178*a(n-17) +171*a(n-18) -156*a(n-19) -88*a(n-20) -98*a(n-21) -154*a(n-22) +74*a(n-23) +127*a(n-24) +19*a(n-25) -63*a(n-26) -13*a(n-27) +26*a(n-28) -a(n-29) +4*a(n-30) -4*a(n-31) for n>33
EXAMPLE
Some solutions for n=5
..0..0..0..1. .0..1..0..1. .0..0..1..1. .0..0..0..1. .0..1..0..0
..1..0..1..1. .0..1..0..1. .1..0..1..0. .1..0..1..1. .1..0..0..1
..1..0..1..0. .0..0..0..1. .1..0..1..0. .1..0..1..0. .0..1..0..1
..1..0..0..0. .0..0..0..1. .0..0..0..0. .1..0..1..1. .1..1..0..1
..1..0..1..1. .1..1..0..1. .1..1..1..0. .0..1..0..0. .1..0..0..1
CROSSREFS
Cf. A303182.
Sequence in context: A281465 A302619 A302411 * A250168 A244870 A309281
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 19 2018
STATUS
approved