func entropy(s) {
    [0] + (s.chars.freq.values »/» s.len) -> reduce { |a,b|
        a - b*b.log2
    }
}

var n_max = 37
var words = ['1', '0']

{
    words.append(words[-1] + words[-2])
} * (n_max - words.len)

say ('%3s %10s %15s  %s' % <N Length Entropy Fibword>...)

for i in ^words {
    var word = words[i]
    say ('%3i %10i %15.12f  %s' % (i+1,
                                   word.len,
                                   entropy(word),
                                   word.len<30 ? word : '<too long>'))
}