haskell problems 007 -> 010

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diff --git a/haskell/010-summation_of_primes.hs b/haskell/010-summation_of_primes.hs
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+-- Summation of primes
+
+-- Problem 10
+-- The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
+
+-- Find the sum of all the primes below two million.
+
+
+main = do
+    print (sum $ eratos_sieve [2..1999999])
+
+eratos_sieve :: [Int] -> [Int]
+eratos_sieve [] = []
+eratos_sieve (x:xs)
+    | x * x > last xs = x:xs
+    | otherwise = x:eratos_sieve [n | n <- xs, n `mod` x /= 0]