A189102 Greatest common divisor of n! and its arithmetic derivative.

1, 1, 1, 4, 4, 48, 48, 192, 1728, 34560, 34560, 414720, 414720, 2903040, 130636800, 2090188800, 2090188800, 25082265600, 25082265600, 501645312000, 31603654656000, 347640201216000, 347640201216000, 5562243219456000, 139056080486400000

Offset

1,4

Links

Nathaniel Johnston, Table of n, a(n) for n = 1..200

Formula

a(n) = gcd(n!,n!') = gcd(A000142(n),A068311(n)).

Example

n = 5: 5! = 120, 120' = 244, gcd(120,244) = 4 -> a(5) = 4

Crossrefs

A068311, A083346, A083346, A085731, A086130, A189100

Sequence in context: A198005 A027501 A341108 * A220778 A364763 A367891

Adjacent sequences: A189099 A189100 A189101 * A189103 A189104 A189105

Keyword

nonn

Author

Giorgio Balzarotti, Apr 16 2011

Status

approved