

A186644


The sum of the oex divisors of n.


2



1, 3, 4, 5, 6, 12, 8, 15, 10, 18, 12, 26, 14, 24, 24, 25, 18, 36, 20, 40, 32, 36, 24, 60, 26, 42, 40, 54, 30, 72, 32, 59, 48, 54, 48, 80, 38, 60, 56, 90, 42, 96, 44, 82, 75, 72, 48, 118, 50, 88, 72, 96, 54, 120, 72, 120, 80, 90
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OFFSET

1,2


COMMENTS

See A186643 for a definition of which divisors of n are classified as oex divisors.


LINKS

Table of n, a(n) for n=1..58.


FORMULA

a(n) >= A049417(n).


MAPLE

maxval := proc(n, d) local nshf, a ; if n mod d <> 0 then 0; else nshf := n ; a := 0 ; while nshf mod d = 0 do nshf := nshf /d ; a := a+1 ; end do: a; end if; end proc:
A186644 := proc(n) a := 1 ; for d in numtheory[divisors](n) minus {1} do if type(maxval(n, d), 'odd') then a := a+d ; end if; end do: a ; end proc: # R. J. Mathar, Mar 04 2011


PROG

(PARI) a(n) = sumdiv(n, d, d*((d==1)  (valuation(n, d) % 2))); \\ Michel Marcus, Feb 06 2016


CROSSREFS

Cf. A186643, A000203, A049417, A050376.
Sequence in context: A241405 A049417 A188999 * A125139 A107224 A026493
Adjacent sequences: A186641 A186642 A186643 * A186645 A186646 A186647


KEYWORD

nonn


AUTHOR

Vladimir Shevelev, Feb 25 2011


STATUS

approved



