A093394 a(n) is the GCD of n and the product of the anti-divisors of n.

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

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