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A033634 OddPowerSigma(n) = sum of odd power divisors of n 2
1, 3, 4, 3, 6, 12, 8, 11, 4, 18, 12, 12, 14, 24, 24, 11, 18, 12, 20, 18, 32, 36, 24, 44, 6, 42, 31, 24, 30, 72, 32, 43, 48, 54, 48, 12, 38, 60, 56, 66, 42, 96, 44, 36, 24, 72, 48, 44, 8, 18, 72, 42, 54, 93, 72, 88, 80, 90, 60, 72, 62, 96, 32, 43, 84, 144, 68, 54, 96, 144 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

If n = Product p(i)^r(i) then opsigma(n) = Product (1+(p(i)^(s(i)+2)-p(i))/(p(i)^2-1)), where si=ri when ri is odd, si=ri-1 when ri is even.

MAPLE

A033634 := proc(n) a := 1 ; for d in ifactors(n)[2] do if type(op(2, d), 'odd') then   s := op(2, d) ; else s := op(2, d)-1 ; end if; p := op(1, d) ; a := a*(1+(p^(s+2)-p)/(p^2-1)) ; end do: a; end proc:

CROSSREFS

Sequence in context: A109506 A000113 A069915 * A111970 A141730 A127737

Adjacent sequences:  A033631 A033632 A033633 * A033635 A033636 A033637

KEYWORD

nonn,mult

AUTHOR

Yasutoshi Kohmoto (zbi74583(AT)boat.zero.ad.jp)

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Last modified February 17 23:58 EST 2012. Contains 206085 sequences.