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Table of n, a(n) for n=0..33.
(PARI) a(n)=sum(k=0, (n+1)\2, k*binomial(n, k))
Sequence in context: A178440 A097965 A075645 * A055259 A032299 A032211
Adjacent sequences: A185249 A185250 A185251 * A185253 A185254 A185255
M. F. Hasler, Jan 24 2012