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 A155361 Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 2,2 3,1 3,3 4,2 4,3 polyhexes in any orientation on a planar nXnXn triangular grid. 0
 1, 7, 19, 37, 61, 398, 3352, 18677, 76887, 524948, 7212413, 105020342, 1220235443, 15236713872, 301443806483, 8288724969974, 237668565804989, 6783028496183063 (list; graph; refs; listen; history; text; internal format)
 OFFSET 4,2 COMMENTS Same series for 1,1 2,0 2,1 3,2 3,3 4,2 4,3 polyhexes. Same series for 1,0 1,1 2,0 2,2 3,0 3,2 4,2 polyhexes. Same series for 1,0 1,1 2,0 2,1 2,2 3,0 3,2 4,2 polyhexes. LINKS Table of n, a(n) for n=4..21. EXAMPLE Maximal 9 X 9 X 9 example ...........0 ..........1.1 .........1.0.1 ........0.1.1.1 .......0.0.1.0.0 ......0.0.0.0.0.0 .....1.1.1.0.1.1.1 ....1.0.1.0.0.1.0.1 ...0.1.1.1.0.1.1.1.0 CROSSREFS Sequence in context: A155409 A155406 A155352 * A155315 A155323 A121091 Adjacent sequences: A155358 A155359 A155360 * A155362 A155363 A155364 KEYWORD nonn AUTHOR R. H. Hardin Jan 22 2009 STATUS approved

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Last modified August 6 13:04 EDT 2024. Contains 374974 sequences. (Running on oeis4.)