A093394 - OEIS

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A093394

a(n) is the GCD of n and the product of the anti-divisors of n.

2

1, 1, 1, 2, 1, 1, 3, 2, 1, 4, 1, 2, 15, 1, 1, 6, 1, 4, 21, 2, 1, 8, 5, 2, 27, 4, 1, 30, 1, 1, 33, 2, 35, 12, 1, 2, 39, 8, 1, 42, 1, 4, 45, 2, 1, 16, 7, 10, 51, 4, 1, 54, 55, 8, 57, 2, 1, 60, 1, 2, 63, 1, 65, 66, 1, 4, 69, 70, 1, 24, 1, 2, 75, 4

(list; graph; refs; listen; history; text; internal format)

OFFSET

3,4

COMMENTS

See A066272 for definition of anti-divisor.

LINKS

Table of n, a(n) for n=3..76.

FORMULA

a(n) = gcd(n, A091507(n)).

EXAMPLE

The anti-divisors of 18 are 4, 5, 7, 12. Hence a(18) = gcd(4*5*7*12, 18) = 6.

CROSSREFS

Cf. A066417, A091507, A093395, A093396.

Sequence in context: A296150 A079673 A124829 * A094363 A124832 A226130

Adjacent sequences: A093391 A093392 A093393 * A093395 A093396 A093397

KEYWORD

nonn

AUTHOR

Lior Manor, Mar 28 2004

STATUS

approved