An interesting homework problem I got - algorithms from the 19th & 3rd century in pseudocode

Gödel numbering pyth-seudocode

Pyth-seudocode time!

erasto(n): // circa 240 BC haha
  a[1] := 0                          
  
  for i := 2 to n do a[i] := 1
	  p := 2
	  
	  while p^2  <  n do
	    j := p^2
	    
	    while (j  <  n) do             
	      a[j] := 0
	      j := j+p
	    
	    repeat p := p+1 until a[p] = 1   

  return(a)

encode(list_numbers): // Encoding
	prime := 2
	summate := 0
	length := count(list_numbers) //how many numbers we working with?
	primes := find_n_primes(length) //get me some primes son
	
	for i in list_numbers: 
		summate += i^(prime) //character to the power of the relevant prime
		prime := erasto(prime)
		i++

	return summate

decode(n, sequence = [], prime = 2): // Decoding
	count := 0

	while (n % prime) == 0 // Primality check
		n /= prime
		count++

	sequence.add(count) // One value decoded
	prime := erasto(prime)
	decode(n, sequence, prime)