Services & ResourcesWolfram ForumsMathGroup Archive

[Date Index] [Thread Index] [Author Index]

Re: How to check whether an infinite set is closed under

• To: mathgroup at smc.vnet.net
• Subject: [mg124288] Re: How to check whether an infinite set is closed under
• From: DrMajorBob <btreat1 at austin.rr.com>
• Date: Mon, 16 Jan 2012 17:05:34 -0500 (EST)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <201201150951.EAA19688@smc.vnet.net>
• Reply-to: drmajorbob at yahoo.com

"Given k positive numbers a_1<a_2<a_3<...<a_k", how do we know what the  
other numbers "a_k + 1, a_k+2, ......" might be?

Bobby

On Sun, 15 Jan 2012 03:51:49 -0600, Rex <aoirex at gmail.com> wrote:

> Given k positive numbers a_1<a_2<a_3<...<a_k, and all integers greater
> than a_k, we want to check whether this set {a_1, a_2, a_3,...a_k, a_k
> + 1, a_k+2, ......} is closed under addition.
>
> Is there any easy way to do this? any functions that we could use in
> Mathematica?
>
> Your help will be greatly appreciated.
>
>


-- 
DrMajorBob at yahoo.com

• References:
  • How to check whether an infinite set is closed under addition?
    • From: Rex <aoirex@gmail.com>