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Re: Super-Increasing List

  • To: mathgroup at smc.vnet.net
  • Subject: [mg40467] Re: Super-Increasing List
  • From: "Carl K. Woll" <carlw at u.washington.edu>
  • Date: Mon, 7 Apr 2003 04:53:35 -0400 (EDT)
  • Organization: University of Washington
  • References: <b6m04c$efg$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

I just thought I would point out that Hanlon's and Rowe's solutions fail to
recognize superincreasing sequences where the first term is negative, as in
the following example:

{-1, 2, 4, 8, 15}

Of course, this may be a pathological case that flip won't worry about.

Carl Woll
Physics Dept
U of Washington

"flip" <flip_alpha at safebunch.com> wrote in message
news:b6m04c$efg$1 at smc.vnet.net...
> Hello,
>
> does a command or module exist which can test a list of values and
determine
> if it is a super-increasing list?
>
> A super-increasing list satifies the conditions:
>
> a.  the list is in increasing order
> b.  each element of the list is greater than the sum of it's previous
> elements
>
> Example:
>
> list = {2, 3, 7, 15, 31}
>
> So check:
>
> a.  It is in  increasing order and
> b.   3 > 2, 7 > 3+ 2, 15 > 7 + 3 + 2 and 31 > 15 + 7 + 3 + 2,
>
> hence the list is super-increasing.
>
> Thanks for any inputs, Flip
>
> To email me, remove "_alpha".
>
>
>




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