Crypto Number in Cryptonia

This problem involves computing the nth Crypto Number in the Cryptonia sequence. The sequence is defined as follows:

\(a_1 = 1, \quad a_2 = 1\), and for \(n \ge 3\), \(a_n = \sum_{i=1}^{n-1} a_i\). In other words, every term from the third onwards is the sum of all the previous terms. For instance, the sequence begins as: 1, 1, 2, 4, 8, ...

Your task is to compute the nth term of this sequence.

Note: You must read input from stdin and write your result to stdout.

inputFormat

The input consists of a single integer n on a single line, where n (\(1 \le n \le 50\)) is the position in the Crypto Number sequence.

outputFormat

Output a single integer: the nth Crypto Number.

1

1