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A279531
Number of nX3 0..2 arrays with no element equal to a strict majority of its horizontal and vertical neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
1
0, 15, 668, 21430, 539596, 12335295, 263171408, 5359546513, 105415261452, 2018539085414, 37834061478768, 696857649181435, 12649926383138654, 226822585839543107, 4024393321769517272, 70751999489862997510
OFFSET
1,2
COMMENTS
Column 3 of A279534.
LINKS
FORMULA
Empirical: a(n) = 42*a(n-1) -504*a(n-2) +143*a(n-3) +20808*a(n-4) +4770*a(n-5) -203441*a(n-6) -320304*a(n-7) -13560*a(n-8) +3177121*a(n-9) +8046300*a(n-10) -4016730*a(n-11) -29077826*a(n-12) -68511462*a(n-13) -18383220*a(n-14) +206345988*a(n-15) +347749728*a(n-16) +153996300*a(n-17) -501890344*a(n-18) -1207478544*a(n-19) -573584184*a(n-20) +839039912*a(n-21) +1261018752*a(n-22) +1034607360*a(n-23) +298977216*a(n-24) -743195904*a(n-25) -670680576*a(n-26) -239702528*a(n-27) -60456960*a(n-28) +205455360*a(n-29) +138137600*a(n-30) -15974400*a(n-31) +24576000*a(n-32) -32768000*a(n-33) for n>35
EXAMPLE
Some solutions for n=4
..0..1..2. .0..1..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0
..2..0..1. .1..0..0. .1..1..2. .0..1..2. .0..1..2. .1..0..2. .0..1..1
..1..0..0. .1..2..1. .0..2..2. .1..0..0. .2..2..0. .1..2..1. .2..0..2
..0..0..1. .1..0..2. .1..0..1. .1..0..1. .1..2..0. .0..1..1. .1..2..1
CROSSREFS
Cf. A279534.
Sequence in context: A223203 A279465 A349889 * A079600 A171113 A166186
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 14 2016
STATUS
approved