+655 What is the sum of the first 121 numbers in Pascal's triangle.
The sum of rows 0 through n is = -1 + 2^(n + 1)=-1 + 2^(15+1) =65,535 ?? Just guessing !!
+129899 The 121st element will be the first number in the 16th row = 1 ... [ I am letting the "1" at the top of the triangle be the first row ]
The sum of the entries in any row will be 2^(r - 1) where r is the row number
So....the sum of the first 121 elements will be
16
Σ 2^(r - 1) + 1 = [ 65535 + 1 ] = 65536
1
