n = int(input()); i = 0 x = 0 s = 0 for i in range(1,n+1): for x in range(i,n +1): if i != x: if (i + x) % 3 == 0 or (i + x) % 7 == 0: s += 1 print(s) /************************************************************** Problem: 1086 User: admin Language: Python Result: Accepted Time:89 ms Memory:34480 kb ****************************************************************/