avoidence.rb Transformation pattern avoidence

avoidence.rb

counting_numbers = Enumerator.new do |yielder|
  (0..1.0/0).each do |number|     yielder.yield number
  end
end

def nilstuff(a,stuff="")
  if(a.nil?)
    return stuff
  else
    return a
  end
end

def canon_trans(trans)
  vals = trans.uniq.sort
  val_hash ={}
  vals.each_with_index{ |n, idx|
     val_hash[n]=idx
  }
  canon =[]
   trans.each{|elt| canon.push(val_hash[elt])}
  return canon
end

def contains(pattern, trans)
      #iterate a k-subset window, sort the subset elts puts it in canonical form for comparison
      trans.combination(pattern.length){|c|

        if canon_trans(c).inspect  == pattern.inspect
          #puts c.inspect
          return c.inspect
        end
      }
  return nil

end

oeis_hash ={}
seen_hash = {}
2.upto(4) do |patt_size|
  counting_numbers.take(patt_size).repeated_permutation(patt_size).each { |p|
    puts "pattern #{p.inspect}"
    if (seen_hash[canon_trans(p).inspect] == nil)
      seen_hash[canon_trans(p).inspect] = true
      seen_hash[canon_trans(p).reverse.inspect] = true
    else
      puts "seen"
      next
    end
    catatrans=[]
    0.upto(7) do |tran_size|
      avoid = 0
      counting_numbers.take(tran_size).repeated_permutation(tran_size).each { |x|
        if (contains(canon_trans(p), x))
        else
          avoid = avoid +1
        end

      }
      catatrans.push(avoid)
    end
    s = catatrans.inspect
    oeis_hash[s] = nilstuff(oeis_hash[s]) + "|" + p.inspect
    puts oeis_hash.keys.inspect
    puts oeis_hash.inspect
  }
end

Output, the Wilf classes for n up to 7 and k = 2,3,4:
{"[1, 1, 2, 6, 24, 120, 720, 5040]"=>"|[0, 0]", "[1, 1, 3, 10, 35, 126, 462, 1716]"=>"|[0, 1]", "[1, 1, 4, 24, 204, 2220, 29520, 463680]"=>"|[0, 0, 0]", "[1, 1, 4, 24, 186, 1745, 19090, 237594]"=>"|[0, 0, 1]|[0, 1, 0]|[0, 1, 1]|[1, 0, 1]", "[1, 1, 4, 26, 210, 1897, 18368, 186636]"=>"|[0, 1, 2]|[0, 2, 1]|[1, 0, 2]", "[1, 1, 4, 27, 252, 3020, 44220, 765030]"=>"|[0, 0, 0, 0]", "[1, 1, 4, 27, 250, 2935, 41676, 693798]"=>"|[0, 0, 0, 1]|[0, 0, 1, 0]|[0, 1, 1, 1]|[1, 0, 1, 1]", "[1, 1, 4, 27, 250, 2915, 40806, 664944]"=>"|[0, 0, 1, 1]", "[1, 1, 4, 27, 252, 2935, 40351, 633864]"=>"|[0, 0, 1, 2]|[0, 0, 2, 1]|[0, 1, 2, 2]|[1, 0, 2, 2]", "[1, 1, 4, 27, 250, 2915, 40746, 661304]"=>"|[0, 1, 0, 1]", "[1, 1, 4, 27, 252, 2935, 40330, 632408]"=>"|[0, 1, 0, 2]|[0, 2, 1, 2]", "[1, 1, 4, 27, 250, 2915, 40766, 662494]"=>"|[0, 1, 1, 0]|[1, 0, 0, 1]", "[1, 1, 4, 27, 252, 2935, 40330, 632352]"=>"|[0, 1, 1, 2]|[0, 1, 2, 1]|[0, 2, 1, 1]|[0, 2, 2, 1]|[1, 0, 0, 2]|[1, 0, 1, 2]|[1, 0, 2, 1]|[1, 1, 0, 2]", "[1, 1, 4, 27, 252, 2935, 40336, 632870]"=>"|[0, 1, 2, 0]|[2, 0, 1, 2]", "[1, 1, 4, 27, 255, 3028, 41979, 647790]"=>"|[0, 1, 2, 3]|[0, 1, 3, 2]|[0, 3, 2, 1]|[1, 0, 2, 3]|[1, 0, 3, 2]|[2, 1, 0, 3]", "[1, 1, 4, 27, 252, 2935, 40300, 630392]"=>"|[0, 2, 0, 1]|[1, 2, 0, 2]", "[1, 1, 4, 27, 255, 3028, 41979, 647826]"=>"|[0, 2, 1, 3]", "[1, 1, 4, 27, 255, 3028, 41972, 647034]"=>"|[0, 2, 3, 1]|[2, 0, 1, 3]", "[1, 1, 4, 27, 255, 3028, 41972, 647006]"=>"|[0, 3, 1, 2]|[1, 2, 0, 3]", "[1, 1, 4, 27, 255, 3028, 41966, 646404]"=>"|[1, 3, 0, 2]"}