Lah numbers

func lah(n, k) {
    stirling3(n, k)
    #binomial(n-1, k-1) * n!/k!     # alternative formula
}

const r = (0..12)

var triangle = r.map {|n| 0..n -> map {|k| lah(n, k) } }
var widths   = r.map {|n| r.map {|k| (triangle[k][n] \\ 0).len }.max }

say ('n\k ', r.map {|n| "%*s" % (widths[n], n) }.join(' '))

r.each {|n|
    var str = ('%-3s ' % n)
    str += triangle[n].map_kv {|k,v| "%*s" % (widths[k], v) }.join(' ')
    say str
}

with (100) {|n|
    say "\nMaximum value from the L(#{n}, *) row:"
    say { lah(n, _) }.map(^n).max
}

Output:

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