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Table of n, a(n) for n=1..39.
a(n) = (A000043(n)-A000040(n))/2.
Cf. A000040, A000043, A153800, A153801, A153802, A153804.
Sequence in context: A097947 A101032 A025271 * A239740 A100404 A103114
Adjacent sequences: A153801 A153802 A153803 * A153805 A153806 A153807
Omar E. Pol, Jan 13 2009
More terms from R. J. Mathar, Mar 14 2009