Find the missing number in the following series. (63, 62, 61, \text{?} , 49, 40, 13)

The pattern is subtract increasing squares: 63 - 1² = 62, 62 - 1² = 61, 61 - 2² = 57, 57 - 4² = 49, 49 - 6² = 13. The squares being subtracted are 1, 1, 4, 16, 36 which follow the pattern 1², 1², 2², 4², 6². Alternatively, looking at differences: -1, -1, -4, -8, -27. The pattern involves subtracting consecutive squares from a sequence. The missing number is 61 - 4 = 57.