18/12/16 20:37:34.86 VvrWecHB.net
>>835 Ruby 1)は省略
require 'prime'
def fuge(n, cand = Prime.to_a(n), h = {}, succ = 0)
c0 = cand[0]
return h[[n, c0]] if h[[n, c0]]
return 0 if n == 0 || !c0 || n < c0
return 1 if n == c0
x = succ == 2019 ? 0 : fuge(n - c0, cand, h, succ + 1)
h[[n, c0]] = fuge(n, cand[1..-1], h) + x
end
p fuge(19) # => 23
p fuge(31) # => 111
p fuge(2019) # => 576202207044176168646563
p fuge(201931, Prime.to_a(31)) # => 4021686887140718864271667825968903