

A296512


a(n) is the largest subpart of the symmetric representation of sigma(n).


1



1, 3, 2, 7, 3, 11, 4, 15, 5, 9, 6, 23, 7, 12, 8, 31, 9, 35, 10, 39, 11, 18, 12, 47, 13, 21, 14, 55
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OFFSET

1,2


COMMENTS

If n is an odd prime (A065091) then a(n) = (n + 1)/2.
If n is a power of 2 (A000079) then a(n) = 2*n  1.
If n is a perfect number (A000396) then a(n) = 2*n  1, assuming there are no odd perfect numbers.
a(n) is also the largest element in the nth row of the triangles A279391, A280851 and A296508.
The symmetric representation of sigma(n) has A001227(n) subparts.
For the definition of the "subpart" see A279387.
For a diagram with the subparts for the first 16 positive integers see A296508.


LINKS

Table of n, a(n) for n=1..28.


EXAMPLE

For n = 15 the subparts of the symmetric representation of sigma(15) are [8, 7, 1, 8], the largest subpart is 8, so a(15) = 8.


CROSSREFS

Shares infinitely many terms with A241558, A241559, A241838, A296513 (and possibly more).
Cf. A000079, A000203, A000225, A000396, A001227, A065091, A196020, A235791, A236104, A237048, A237591, A237593, A245092, A279387, A279391, A280850, A280851, A296508.
Sequence in context: A276466 A289336 A324509 * A241558 A295422 A241838
Adjacent sequences: A296509 A296510 A296511 * A296513 A296514 A296515


KEYWORD

nonn,more


AUTHOR

Omar E. Pol, Feb 10 2018


STATUS

approved



