path: root/challenge-052/richard-park/apl/ch-1.aplf

 SteppingNo←{
⍝ All stepping numbers from ⍺ to ⍵ inclusive
⍝ 123 is a stepping number; 432 is also; 349 is not.
     i⌷⍨⊂⍸{1=∧/2-/⍎¨⍕⍵}¨i←⍺+⍳⍵-⍺
 }