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A104252
Number of oriented prime alternating tangles.
0
1, 2, 7, 29, 137, 679, 3515, 18677, 101463, 560062, 3132639, 17708417, 100998567, 5803646663, 3356435363, 19519575163
OFFSET
1,2
CROSSREFS
Sequence in context: A064641 A183608 A307389 * A373802 A018977 A190736
KEYWORD
nonn,hard
AUTHOR
Ralf Stephan, Feb 27 2005
STATUS
approved