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A271968
Number of ways to move elements of an nXnXn triangular array to themselves or a neighbor, with no more than 7-1 2-cycles.
0
1, 6, 61, 2267, 215138, 59705923, 44635673507, 89688682304014, 473147967693970583
OFFSET
1,2
COMMENTS
Column 7 of A271969.
EXAMPLE
Some solutions for n=4
.....5........6........0........0........5........0........0........0
....4.1......0.1......4.3......5.5......6.1......4.3......4.3......5.3
...0.6.0....6.3.5....0.4.3....2.2.6....5.5.1....6.0.5....6.6.3....4.2.6
..4.3.1.0..0.2.2.0..4.3.0.0..4.3.2.3..2.4.2.0..0.1.4.1..0.1.4.1..0.4.3.1
Element moves: 0=itself 1=nw 2=ne 3=w 4=e 5=sw 6=se, reciprocals total 7
CROSSREFS
Cf. A271969.
Sequence in context: A271683 A271966 A271967 * A022502 A272956 A243643
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 17 2016
STATUS
approved