Hi,

Reading this subject and surfing to 
  http://ostermiller.org/calc/sum.html,
I did notice that not all the examples given there
come up with the same result using the two verbs
mentioned in the thread started by Mike Day:

mrs =: >./@(- <./\)@(+/\)

mis =: [: >./ [: (0 >. +)/\. 0 ,~ ]

------>
  (mrs-:mis) 1 2 3 4 5
0

  mrs 1 2 3 4 5
14

  mis 1 2 3 4 5
15

The last one should be the answer according to Ostermiller?
This phenomenon seems to occur when all elements are > 0.

I made a kind of adjustment to the verb 'mrs' more or less
based on the rightmost part of the verb 'mis'. In other words
prefixing the sequence with a zero. 

   mrs2 =: >./@(- <./\)@(+/\)@(0,])  


   mrs2 2 4 9 12
27
   mis 2 4 9 12
27
   mrs2 2 _4 9 _12
9
   mis 2 _4 9 _12
9

So, when the sequence is an alternating one, then
no difference will be noticed between mrs and mis?


Greetings

@@1<=>arie



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