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A186644 The sum of the oex divisors of n. 2

%I

%S 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,

%T 42,40,54,30,72,32,59,48,54,48,80,38,60,56,90,42,96,44,82,75,72,48,

%U 118,50,88,72,96,54,120,72,120,80,90,60,166,62,96,101,117,84,144,68,124,96,144,72,186,74,114,119,138,96

%N The sum of the oex divisors of n.

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

%H Antti Karttunen, <a href="/A186644/b186644.txt">Table of n, a(n) for n = 1..16384</a>

%F a(n) >= A049417(n).

%p 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:

%p 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

%t Table[DivisorSum[n, # &, Or[# == 1, OddQ@ IntegerExponent[n, #]] &], {n, 77}] (* _Michael De Vlieger_, Nov 23 2017 *)

%o (PARI) a(n) = sumdiv(n, d, d*((d==1) || (valuation(n, d) % 2))); \\ _Michel Marcus_, Feb 06 2016

%Y Cf. A186643, A000203, A049417, A050376.

%K nonn

%O 1,2

%A _Vladimir Shevelev_, Feb 25 2011

%E More terms from _Antti Karttunen_, Nov 23 2017

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Last modified November 17 13:33 EST 2019. Contains 329230 sequences. (Running on oeis4.)