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A078320 Sum of all prime factors of n*rad(n)+1, where rad=A007947 (squarefree kernel). 4
2, 5, 7, 6, 15, 37, 12, 17, 11, 101, 63, 73, 24, 197, 115, 14, 36, 109, 183, 70, 32, 102, 60, 34, 15, 677, 43, 134, 423, 70, 52, 18, 116, 102, 615, 38, 144, 39, 763, 401, 60, 358, 49, 39, 30, 102, 37, 34, 49, 170, 1303, 55, 288, 23, 108, 162, 30, 678, 1743, 1801 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n)=A001414(A078310(n)).

LINKS

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

PROG

(PARI) rad(n)=my(f=factor(n)[, 1]); prod(i=1, #f, f[i])

a(n)=my(f=factor(n*rad(n)+1)); sum(i=1, #f~, f[i, 1]*f[i, 2]) \\ Charles R Greathouse IV, Jul 15 2013

(Haskell)

a078320 = a001414 . a078310  -- Reinhard Zumkeller, Jul 23 2013

CROSSREFS

Cf. A078319, A078318, A078314.

Sequence in context: A167554 A202392 A290410 * A306992 A325437 A141430

Adjacent sequences:  A078317 A078318 A078319 * A078321 A078322 A078323

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Nov 23 2002

STATUS

approved

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Last modified February 27 03:03 EST 2020. Contains 332299 sequences. (Running on oeis4.)