

A296513


a(n) is the smallest subpart of the symmetric representation of sigma(n)


1



1, 3, 2, 7, 3, 1, 4, 15, 3, 9, 6, 5, 7, 12, 1, 31, 9, 2, 10, 3, 5, 18, 12, 13, 5, 21, 6, 1
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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) = 1 assuming there are no odd perfect numbers.
a(n) is also the smallest number in the nth row of the triangles A279391 and A280851.
a(n) is also the smallest nonzero term in the nth row of triangle 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 smallest subpart is 1, so a(15) = 1.


CROSSREFS

Shares infinitely many terms with A241558, A241559, A241838, A296512 (and possibly more).
Cf. A000079, A000203, A000225, A000396, A001227, A065091, A099378, A196020, A235791, A236104, A237048, A237591, A237593, A245092, A279387, A279391, A280850, A280851, A296508.
Sequence in context: A266664 A308439 A245601 * A099378 A182885 A182891
Adjacent sequences: A296510 A296511 A296512 * A296514 A296515 A296516


KEYWORD

nonn,more


AUTHOR

Omar E. Pol, Feb 10 2018


STATUS

approved



