The infinite sequence \(S=\{s_1,s_2,s_3,\ldots\}\) is defined by \(s_1=7\) and \(s_n=7^{s_{n-1}}\) for each integer \(n>1\) . What is the remainder when \(s_{100}\) is divided by \(5\) ?
The remainder is 1.
+140 
