document.write( "Question 823184: I have a sequence, which I can't really find an explicit formula for. The sequence is 1,3,7,15,31,63... I found the recursive formula which is 2n+1. But how do I find the explicit formula if it's not geometric nor arithmetic? \n" ); document.write( "
Algebra.Com's Answer #495736 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
a_n = -1+2^n (for all terms given)
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