A sequence of positive real numbers a_1, a_2, a_3... has the property that for i>=2, each a_i is equal to the sum of all the previous terms. If a_19=91, then what is a_20?
+36915 The summation for n = 19 is usually 190
this sequence is only 91
190x =91
x = 91/190 so the numbers in the sequence are reduced by this multiplier
\( \sum_{1}^{20} ( 91/190) n = 100.578947368\) This would be a20
