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Re: Super-Increasing List

• To: mathgroup at smc.vnet.net
• Subject: [mg40456] Re: Super-Increasing List
• From: Bill Rowe <listuser at earthlink.net>
• Date: Sun, 6 Apr 2003 04:34:30 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

On 4/5/03 at 4:00 AM, flip_alpha at safebunch.com (flip) wrote:


>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}

SuperIncreasingQ[data_List] :=
  And @@ Flatten[{OrderedQ[data],
   MapThread[OrderedQ[{#1, #2}] &, 
     {Drop[FoldList[Plus, 0, data], -1], data}]}]
 
 SuperIncreasingQ[list]
 True

• Follow-Ups:
  • Re: Re: Super-Increasing List
    • From: Dr Bob <majort@cox-internet.com>