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A049599 Number of (1+e)-divisors of n: if n = Product p(i)^r(i), d = Product p(i)^s(i) and s(i) = 0 or s(i) divides r(i), then d is a (1+e)-divisor of n. 11
1, 2, 2, 3, 2, 4, 2, 3, 3, 4, 2, 6, 2, 4, 4, 4, 2, 6, 2, 6, 4, 4, 2, 6, 3, 4, 3, 6, 2, 8, 2, 3, 4, 4, 4, 9, 2, 4, 4, 6, 2, 8, 2, 6, 6, 4, 2, 8, 3, 6, 4, 6, 2, 6, 4, 6, 4, 4, 2, 12, 2, 4, 6, 5, 4, 8, 2, 6, 4, 8, 2, 9, 2, 4, 6, 6, 4, 8, 2, 8, 4, 4, 2, 12, 4, 4, 4, 6, 2, 12, 4, 6, 4, 4, 4, 6, 2, 6, 6, 9, 2, 8, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

FORMULA

If n = Product p(i)^r(i) then a(n) = Product (tau(r(i))+1), where tau(n) = number of divisors of n, cf. A000005. - Vladeta Jovovic, Apr 29 2001

MATHEMATICA

a[n_] := Times @@ (DivisorSigma[0, #] + 1 &)  /@ FactorInteger[n][[All, 2]]; a[1] = 1; Table[a[n], {n, 1, 103}] (* Jean-Fran├žois Alcover, Oct 10 2011 *)

PROG

(Haskell)

a049599 = product . map ((+ 1) . a000005 . fromIntegral) . a124010_row

-- Reinhard Zumkeller, Mar 13 2012

CROSSREFS

Cf. A049603, A051378.

Cf. A124010, A000005, A049419.

Sequence in context: A073184 A073182 A282446 * A305461 A043261 A157986

Adjacent sequences:  A049596 A049597 A049598 * A049600 A049601 A049602

KEYWORD

nonn,easy,nice,mult

AUTHOR

Yasutoshi Kohmoto

EXTENSIONS

More terms from Naohiro Nomoto, Apr 12 2001

STATUS

approved

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Last modified February 19 18:51 EST 2019. Contains 320328 sequences. (Running on oeis4.)