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A078318 Sum of divisors of n*rad(n)+1, where rad=A007947 (squarefree kernel). 5
3, 6, 18, 13, 42, 38, 93, 18, 56, 102, 186, 74, 324, 198, 342, 48, 540, 110, 546, 272, 756, 588, 972, 180, 312, 678, 126, 528, 1266, 972, 1596, 84, 1980, 1260, 1842, 256, 2484, 1842, 2286, 402, 2613, 2124, 3534, 1440, 1281, 2220, 4536, 307, 660, 672 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n)=A000203(A078310(n)).

LINKS

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

PROG

(PARI) rad(n)=vecprod(factor(n)[, 1])

a(n)=sigma(n*rad(n)+1) \\ Charles R Greathouse IV, Jul 09 2013

(Haskell)

a078318 = a000203 . a078310  -- Reinhard Zumkeller, Jul 23 2013

CROSSREFS

Cf. A078317, A078319, A078320.

Sequence in context: A274103 A195995 A248324 * A193433 A074370 A174101

Adjacent sequences:  A078315 A078316 A078317 * A078319 A078320 A078321

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Nov 23 2002

STATUS

approved

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Last modified January 28 13:25 EST 2020. Contains 331321 sequences. (Running on oeis4.)