

A039725


Even abundant numbers divided by 2.
(Formerly N1690)


3



6, 9, 10, 12, 15, 18, 20, 21, 24, 27, 28, 30, 33, 35, 36, 39, 40, 42, 44, 45, 48, 50, 51, 52, 54, 56, 57, 60, 63, 66, 69, 70, 72, 75, 78, 80, 81, 84, 87, 88, 90, 93, 96, 98, 99, 100, 102, 104, 105, 108, 110, 111, 112, 114, 117, 120, 123, 126, 129, 130, 132, 135, 136
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OFFSET

1,1


COMMENTS

While the first even abundant number is 12 = 2^2*3, the first odd abundant is 945 = 3^3*5*7, the 232nd abundant number!


REFERENCES

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).


LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000


FORMULA

a(n) = A173490(n) / 2.


EXAMPLE

The first even abundant number is 12, so 12/2 = 6 is the first element in this sequence.


CROSSREFS

Cf. A005101, A005231, A173490.
Sequence in context: A177201 A090466 A090428 * A262362 A125494 A177029
Adjacent sequences: A039722 A039723 A039724 * A039726 A039727 A039728


KEYWORD

easy,nonn


AUTHOR

N. J. A. Sloane. This was included in the 1973 "Handbook", but was then dropped from the database. Resubmitted by James A. Sellers. Entry revised by N. J. A. Sloane, Jun 12 2012


EXTENSIONS

Corrected and edited by Daniel Forgues, Nov 22 2010


STATUS

approved



