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Table of n, a(n) for n=2..40.
a(n) = A000990(n)-A000041(n).
Column 2 of A091355. Cf. A000219, A091357-A091360.
Sequence in context: A184353 A019135 A069957 * A107705 A278690 A002883
Adjacent sequences: A091353 A091354 A091355 * A091357 A091358 A091359
Christian G. Bower, Jan 02 2004