⍀
N⍀Y expands first-axis cells.
N⍀Y
1 0 1⍀2 2⍴⍳4 ⍝ 3 2⍴1 2 0 0 3 4
f⍀Y scans down the first axis.
f⍀Y
+⍀2 3⍴⍳6 ⍝ 2 3⍴1 2 3 5 7 9
S f⍀Y supplies a seed.
S f⍀Y
10 20+⍀2 2⍴⍳4 ⍝ 2 2⍴11 22 14 26
Counts, seeds and [K] follow \.
[K]
\