Re: combinations problem
- To: mathgroup at smc.vnet.net
- Subject: [mg130654] Re: combinations problem
- From: Dana DeLouis <dana01 at icloud.com>
- Date: Tue, 30 Apr 2013 04:17:44 -0400 (EDT)
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On Sunday, April 28, 2013 5:17:32 AM UTC-4, Ray Koopman wrote:
> I want to select 6 combinations from numbers 1 to 49 with condition that its sum equal 152,
> Timing@Length@Select[IntegerPartitions[152,{6},Range@49],Unequal@@#&]
>
> {1.86, 165490}
>
Hi. Just an interesting way to confirm the number of solutions:
Timing[Coefficient[Expand[Coefficient[
Product[k*t^n + 1, {n, 49}], k, 6]], t, 152]]
{0.079659,165490}
= = = = = = = = = =
HTH :>)
Dana DeLouis
Mac & Mathematica 9
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