link strings   # to get csort()

procedure main(A)
    limit := A[1] | 1000000             # Allow alternate limit
    mSq := 0
    # May have multiple 'unique' sequence sets (unrelated seeds) so use table
    every s := [n := 1 to limit, sequence(n)] do {
        if mSq <:= *s[2] then mT := table()   # new max, start over
        if mSq  == *s[2] then insert((/mT[n := csort(n)] := set()) | mT[n],s)
        }
    dumpSequences(mT)
end

procedure sequence(n)                   # produce sequence of SDS with seed n
    every (repeats := [], iter := seq(), put(repeats, n)) do
        if (n := nElem(n)) == !repeats then return repeats   # Converged
end

procedure nElem(n)	                # given n, produce its self-description
    every (n1 := "", c := !cset(n)) do
        (every (d := 0) +:= (upto(c, n),1)) | (n1 := d||c||n1)
    return n1
end

procedure dumpSequences(seqTab)		# Show each 'unique' sequence in table
    every writes("Seeds:" | (!!seqTab)[1], " ")
    write("\n\nIterations: ",*(!!seqTab)[2])
    every s := !seqTab do (write() & every write(!(!s\1)[2]))
end