The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A056596 Number of nonsquare divisors of n!. 1

%I

%S 0,1,3,6,14,24,54,88,148,240,510,756,1548,2520,3936,5248,10624,14508,

%T 29196,40740,60500,95400,191400,242016,338880,529920,674688,912912,

%U 1830192,2327424,4660224,5523456,7858176,12152064,16406592,19576080

%N Number of nonsquare divisors of n!.

%H Amiram Eldar, <a href="/A056596/b056596.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = d(n!) - A046951(n!)

%F a(n) = A027423(n) - A055993(n). - _Amiram Eldar_, Jul 16 2019

%t Table[Count[Divisors[n!], d_ /; !IntegerQ@ Sqrt@ d], {n, 30}] (* _Amiram Eldar_, Jul 16 2019 after _Michael De Vlieger_ at A055993 *)

%o (MAGMA) [#[d:d in Divisors(Factorial(n))| not IsSquare(d)]:n in [1..36]]; // _Marius A. Burtea_, Jul 16 2019

%Y A000142, A000005, A046951, A055772, A027423, A055993.

%K nonn

%O 1,3

%A _Labos Elemer_, Jul 21 2000

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified January 22 07:30 EST 2020. Contains 331139 sequences. (Running on oeis4.)