Sieve of Eratosthenes

sieve.hs

primes = take 15 (sieve [2..])

sieve (prime:rest) = prime : sieve [x | x <- rest, mod x prime /= 0]

sieve.js

const sieve = ([prime, ...rest]) =>
  prime ? [prime, ...sieve(rest.filter(x => x % prime !== 0))] : []

const primes = sieve([2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, /* ... */])

sieve.py

def sieve (prime = None, *rest):
  if not prime: return []
  return [prime, *sieve(*[x for x in rest if x % prime != 0])]

primes = sieve(*range(2, 30))