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Re: How to count

• To: mathgroup at smc.vnet.net
• Subject: [mg125719] Re: How to count
• From: "Harvey P. Dale" <hpd1 at nyu.edu>
• Date: Fri, 30 Mar 2012 04:31:50 -0500 (EST)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <201203290755.CAA21655@smc.vnet.net>

Artur:

	Your code requires computing n! twice for each n.  You might try
something like this instead:

	ss[n_]:=Module[{nf=n!},(Floor[Sqrt[nf]]+1)^2-nf]

But for large n, Mathematica cannot compute n! because of overflow.

	Best,

	Harvey


-----Original Message-----
From: Artur [mailto:grafix at csl.pl]
Sent: Thursday, March 29, 2012 3:55 AM
To: mathgroup at smc.vnet.net
Subject: [mg125719] How to count

Dear Mathematica Gurus!

I have seriously problem with counting distances between smallest square
bigger than n! (for big n) e.g.

aa = {}; Do[k = 1 + Floor[Sqrt[n!]]; kk = k^2 - n!; Print[kk];
  kkk = N[Log[kk], 100]; Print[kkk];
  AppendTo[aa, kkk], {n, 1, 10000000, 1000000}]; aa

Who have idea how to count this on Mathematica?

Best wishes
Artur

• References:
  • How to count
    • From: Artur <grafix@csl.pl>