Solve problem 751.

python/e751.py

@@ -0,0 +1,35 @@
+from math import floor
+
+
+def next_b(b_prev):
+    b = floor(b_prev) * (b_prev - floor(b_prev) + 1)
+    return b
+
+
+def euler_751():
+
+    min_found = 2
+    theta_str_orig = "2."
+    while len(theta_str_orig) < 26:
+        for n in range(min_found, 1000):
+            theta_str_new = str(theta_str_orig) + str(n)
+            b = float(theta_str_new)
+            theta_str = theta_str_new.replace("2.", "")
+            while theta_str != "":
+                b = next_b(b)
+                a_str = str(floor(b))
+                # print(a_str, theta_str)
+                if theta_str.startswith(a_str):
+                    theta_str = theta_str.replace(a_str, "", 1)
+                else:
+                    break
+            if theta_str == "":
+                theta_str_orig = theta_str_new
+                break
+    return theta_str_orig
+
+
+if __name__ == "__main__":
+    solution = euler_751()
+    print("e751.py: " + str(solution))
+    assert solution == "2.223561019313554106173177"