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a(n) = 2*(n-1) for n > 6.
Table of n, a(n) for n=0..66.
Sequence in context: A084138 A127141 A014406 * A231219 A231343 A121924
Adjacent sequences: A154423 A154424 A154425 * A154427 A154428 A154429
Reinhard Zumkeller, Jan 09 2009