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A316307
Number of nX4 0..1 arrays with every element unequal to 0, 1, 3, 4, 6 or 8 king-move adjacent elements, with upper left element zero.
1
5, 17, 21, 74, 148, 404, 1046, 3023, 8295, 24149, 72052, 216111, 652104, 2002615, 6178078, 19140977, 59556817, 186014195, 582148144, 1824951156, 5729180734, 18006356728, 56634356929, 178236709353, 561215535231, 1767752144844
OFFSET
1,1
COMMENTS
Column 4 of A316311.
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) -25*a(n-2) +52*a(n-3) -108*a(n-4) +171*a(n-5) -167*a(n-6) +43*a(n-7) +395*a(n-8) -1327*a(n-9) +3351*a(n-10) -5073*a(n-11) +4368*a(n-12) -3553*a(n-13) -1020*a(n-14) +5703*a(n-15) -12739*a(n-16) +7338*a(n-17) +39157*a(n-18) -66903*a(n-19) +103005*a(n-20) -110427*a(n-21) +66905*a(n-22) -4484*a(n-23) -159644*a(n-24) +97258*a(n-25) -134507*a(n-26) +374090*a(n-27) +1159495*a(n-28) -2391704*a(n-29) +2459451*a(n-30) -2230610*a(n-31) -5458771*a(n-32) +7569293*a(n-33) -10320673*a(n-34) +19970165*a(n-35) -9391600*a(n-36) -1076499*a(n-37) +7210061*a(n-38) -12705453*a(n-39) +37281810*a(n-40) -40002110*a(n-41) +18704452*a(n-42) -23626754*a(n-43) -2064967*a(n-44) -18460738*a(n-45) -8187365*a(n-46) +44187148*a(n-47) +16963411*a(n-48) +5511538*a(n-49) -21111103*a(n-50) -2213737*a(n-51) +3119256*a(n-52) +370852*a(n-53) -3258556*a(n-54) -3875250*a(n-55) +956158*a(n-56) +865515*a(n-57) +672269*a(n-58) -137193*a(n-59) +153524*a(n-60) +18277*a(n-61) -5810*a(n-62) -20204*a(n-63) -3516*a(n-64) -4760*a(n-65) -288*a(n-66) +384*a(n-67) for n>68
EXAMPLE
Some solutions for n=5
..0..0..1..1. .0..0..0..0. .0..0..0..0. .0..0..0..0. .0..1..0..1
..1..0..1..0. .0..0..0..1. .1..0..0..1. .0..1..0..0. .1..1..0..0
..1..0..0..0. .0..1..0..1. .1..1..0..1. .0..0..0..0. .1..1..0..0
..0..0..0..0. .0..0..0..1. .1..1..0..0. .0..0..0..0. .1..1..0..0
..0..0..0..0. .0..0..0..0. .1..0..0..0. .1..0..0..0. .1..0..1..0
CROSSREFS
Cf. A316311.
Sequence in context: A145818 A029986 A076275 * A317262 A031270 A022141
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 29 2018
STATUS
approved