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A152678
Even members of A000203.
5
4, 6, 12, 8, 18, 12, 28, 14, 24, 24, 18, 20, 42, 32, 36, 24, 60, 42, 40, 56, 30, 72, 32, 48, 54, 48, 38, 60, 56, 90, 42, 96, 44, 84, 78, 72, 48, 124, 72, 98, 54, 120, 72, 120, 80, 90, 60, 168, 62, 96, 104, 84, 144, 68, 126, 96, 144
OFFSET
1,1
COMMENTS
a(n) = sigma(A028983(n)) = A000203(A028983(n)). [From Jaroslav Krizek, Oct 06 2009]
MATHEMATICA
Select[DivisorSigma[1, Range[100]], EvenQ] (* Harvey P. Dale, Jun 18 2017 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Omar E. Pol, Dec 10 2008
STATUS
approved