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A099636 a(n) = gcd(sum of all prime factors of n, product of all prime factors of n). 2
1, 2, 3, 2, 5, 1, 7, 2, 3, 1, 11, 1, 13, 1, 1, 2, 17, 1, 19, 1, 1, 1, 23, 1, 5, 1, 3, 1, 29, 10, 31, 2, 1, 1, 1, 1, 37, 1, 1, 1, 41, 6, 43, 1, 1, 1, 47, 1, 7, 1, 1, 1, 53, 1, 1, 1, 1, 1, 59, 10, 61, 1, 1, 2, 1, 2, 67, 1, 1, 14, 71, 1, 73, 1, 1, 1, 1, 6, 79, 1, 3, 1, 83, 6, 1, 1, 1, 1, 89, 10, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..93.

EXAMPLE

n=84: a(84) = gcd(2*3*7, 2+3+7) = gcd(42, 12) = 6.

MATHEMATICA

PrimeFactors[n_Integer] := Flatten[ Table[ # [[1]], {1}] & /@ FactorInteger[n]]; f[n_] := Block[{pf = PrimeFactors[n]}, GCD[Plus @@ pf, Times @@ pf]]; Table[ f[n], {n, 93}] (* Robert G. Wilson v, Nov 04 2004 *)

CROSSREFS

Cf. A099634, A099635.

Sequence in context: A157753 A020500 A014963 * A099635 A178380 A178375

Adjacent sequences:  A099633 A099634 A099635 * A099637 A099638 A099639

KEYWORD

nonn

AUTHOR

Labos Elemer, Oct 28 2004

STATUS

approved

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Last modified September 19 21:42 EDT 2020. Contains 337184 sequences. (Running on oeis4.)