# project euler 52
# check n, 2n, ..., 6n to see if they
# are all permutations of the same digits.
# int ? bool
c ← (
  ×+1⇡6  # get multiples n, 2n, ...
  ⍚(⍆°⋕) # sort digits
  /↧⧈₂/≍ # pairwise match digits
)

⍢+₁(¬c)1 # increment n until c(n) = 1