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a(n) are powers of 3.
Table of n, a(n) for n=0..21.
a(n) = 3^n*a(floor(n/3)). - Vladeta Jovovic, Mar 01 2004
Sequence in context: A139731 A259986 A124049 * A171557 A055156 A047912
Adjacent sequences: A067620 A067621 A067622 * A067624 A067625 A067626
Benoit Cloitre, Feb 02 2002