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A264947
Number of 4 X n arrays containing n copies of 0..4-1 with no equal horizontal neighbors and new values introduced sequentially from 0.
1
1, 60, 3201, 184740, 11375145, 730983420, 48402531561, 3282992503164, 226854309720993, 15915758107113276, 1130694005695927761, 81177583723495750340, 5880587303767912833417, 429300706847441007321756
OFFSET
1,2
COMMENTS
Row 4 of A264945.
LINKS
Christoph Koutschan, Table of n, a(n) for n = 1..80 (first 20 terms from R. H. Hardin).
M. Kauers and C. Koutschan, Some D-finite and some possibly D-finite sequences in the OEIS, arXiv:2303.02793 [cs.SC], 2023.
EXAMPLE
Some solutions for n=4:
0 1 0 2 0 1 2 0 0 1 2 0 0 1 0 1 0 1 2 0
2 0 3 1 3 0 1 2 0 3 1 3 0 2 3 1 3 1 0 3
2 3 2 1 3 2 3 1 3 2 0 1 3 1 3 2 2 3 1 2
1 3 0 3 1 2 3 0 2 1 2 3 2 0 2 3 3 1 0 2
MATHEMATICA
cols = Tuples[{0, 1, 2, 3}, 4];
tmat = Table[If[Or @@ MapThread[SameQ, cols[[{i, j}]]], 0, 1], {i, 256}, {j, 256}];
vec = vvec = ((x^Count[#, 0] * y^Count[#, 1] * z^Count[#, 2]) & /@ cols);
Prepend[Table[vec = Expand[vvec*(tmat.vec)]; Coefficient[Total[vec], (x*y*z)^n]/24, {n, 2, 10}], 1]
CROSSREFS
Cf. A264945.
Sequence in context: A084659 A230568 A180373 * A004297 A223657 A264369
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 29 2015
STATUS
approved