P.S. Here are the same takes listed horizontally, easier to cut and paste.
(iii0,:iii1) 10
1 4 7 10 13 16 19 22 25 28
0 4 20 54 112 200 324 490 704 972
(v0,:v1) 10
1 6 31 76 141 226 331 456 601 766
0 _6 _32 _108 _384 _1250 _3456 _8232 _17408 _33534
Kip Murray wrote:
> wow
>
> Also, one may propose a favorite sequence. I have two pairs to offer. The
> first pair is almost too easy. The second pair is harder but you may get it
> if
> you understand the first pair. Provide definitions for the verb pair iii0,
> iii1
> and the pair v0, v1 . Each verb generates takes from a sequence:
>
> (iii0,.iii1) 10 NB. takes listed vertically
> 1 0
> 4 4
> 7 20
> 10 54
> 13 112
> 16 200
> 19 324
> 22 490
> 25 704
> 28 972
>
> (v0,.v1) 10
> 1 0
> 6 _6
> 31 _32
> 76 _108
> 141 _384
> 226 _1250
> 331 _3456
> 456 _8232
> 601 _17408
> 766 _33534
>
> If you use J to help figure these out, tell!
>
>
> Roger Hui wrote:
>> p:@(+/)@(i.!])@>@i.
>>
>> Why is it my favorite? The function does not contain
>> any of the digits 0-9.
>>
>>
>>
>> ----- Original Message -----
>> From: Kip Murray <[email protected]>
>> Date: Monday, August 17, 2009 12:16
>> Subject: Re: [Jprogramming] Takes from a mystery sequence
>> To: Programming forum <[email protected]>
>>
>>> Part three: Propose your favorite
>>>
>>> Kip Murray wrote:
>>>> Part two: If you used J to help you figure out the sequence, tell
>>>>
>>>> Kip Murray wrote:
>>>>> Verb i. produces takes from the sequence of non-negative integers:
>>>>>
>>>>> i.20
>>>>> 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
>>>>> i.5
>>>>> 0 1 2 3 4
>>>>> 5 {. i.20
>>>>> 0 1 2 3 4
>>>>>
>>>>> Verb s generates takes from a mystery sequence (no peeking in
>>> Sloane, please)
>>>>> s 13
>>>>> 2 3 7 19 53 131 311 719 1619 3671 8161 17863 38873
>>>>> s 5
>>>>> 2 3 7 19 53
>>>>> 5 {. s 13
>>>>> 2 3 7 19 53
>>>>>
>>>>> Your mission, should you decide to accept it, is to provide a
>>> definition for s .
>>>>> As always, these instructions will
>> ----------------------------------------------------------------------
>> For information about J forums see http://www.jsoftware.com/forums.htm
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
