OFFSET
1,1
COMMENTS
Also, even numbers of A239929 divided by two.
First differs from A101550 at a(51). - R. J. Mathar, Oct 04 2018
FORMULA
a(n) = A244894(n)/2.
EXAMPLE
5 is in the sequence because 10 is a composite number, and the symmetric representation of sigma(10) = 18 has two parts (as shown below), and 10/2 = 5.
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. _ _ _ _ _ _ 9
. |_ _ _ _ _ |
. | |_
. |_ _|_
. | |_ _ 9
. |_ _ |
. | |
. | |
. | |
. | |
. |_|
.
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Oct 04 2018
STATUS
approved