Sequence
From NARS2000


L is a numeric or nested scalar or one or twoelement vector consisting of starting value(s) and optional step value(s) (default is 1) for the sequence.  
R is a numeric or nested scalar or oneelement vector consisting of ending value(s) for the sequence.  
Z is an array whose values represent the sequence of values between L and R. 
For example
3..10 Start and end values 3 4 5 6 7 8 9 10 3 2..10 Start, step, and end values 3 5 7 9 (⊂3 4)..6 Two start values, so the result is twodimensional and nested 3 4 3 5 3 6 4 4 4 5 4 6 5 4 5 5 5 6 6 4 6 5 6 6 3..⊂5 6 Two ending values, so the result is twodimensional and nested 3 3 3 4 3 5 3 6 4 3 4 4 4 5 4 6 5 3 5 4 5 5 5 6
The starting value(s) may be greater than the ending values in which case the sequence is in descending order. The sign of the optional step value is ignored.
(6 7)2..2 6 7 6 5 6 3 4 7 4 5 4 3 2 7 2 5 2 3
This primitive was suggested by John Scholes of Dyalog, Ltd.