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1,2
Column 4 of A217891
Table of n, a(n) for n=1..14.
Some solutions for n=4
..1....4....1....2....2....1....1....1....3....4....3....1....4....1....1....1
..3....1....4....2....2....2....2....1....3....3....2....1....2....1....3....3
..2....1....2....1....3....4....2....3....1....1....2....2....1....1....3....4
..2....1....2....1....1....3....2....3....1....1....1....4....1....3....2....2
Sequence in context: A049172 A049155 A063024 * A151129 A151130 A216949
Adjacent sequences: A217884 A217885 A217886 * A217888 A217889 A217890
nonn
R. H. Hardin Oct 14 2012
approved