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+###
+# Prime permutations
+# Problem 49
+#
+# The arithmetic sequence, 1487, 4817, 8147, in which each of the terms increases by 3330, is unusual in two ways: (i) each of the three terms are prime, and, (ii) each of the 4-digit numbers are permutations of one another.
+# There are no arithmetic sequences made up of three 1-, 2-, or 3-digit primes, exhibiting this property, but there is one other 4-digit increasing sequence.
+# What 12-digit number do you form by concatenating the three terms in this sequence?
+###
+
+
+import math
+
+
+def is_prime(n):
+    if n % 2 == 0 or n % 3 == 0 or n % 5 == 0:
+        return False
+    for d in range(6, math.floor(math.sqrt(n)) + 1, 6):
+        if n % (d - 1) == 0 or n % (d + 1) == 0:
+            return False
+    return True
+
+
+for n1 in range(1001, 10000, 2):
+    for n2 in range(n1 + 2, 10000, 2):
+        n3 = n2 + (n2 - n1)
+        s = sorted(str(n1))
+        if s != sorted(str(n2)) or s != sorted(str(n3)):
+            continue
+        if is_prime(n1) and is_prime(n2) and is_prime(n3):
+            print(n1, n2, n3)
+
+