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Table of n, a(n) for n=0..32.
a(n) = sigma(A001006(n)) = A000203(A001006(n)).
A152981 := proc(n) numtheory[sigma](A001006(n)) ; end proc:
seq(A152981(n), n=0..40) ; # R. J. Mathar, Jul 08 2011
Cf. A000005, A000203, A001006, A152761.
Sequence in context: A023195 A100382 A222227 * A112040 A222187 A084611
Adjacent sequences: A152978 A152979 A152980 * A152982 A152983 A152984
Omar E. Pol, Dec 20 2008