First differences of A140322.

Terms

a(0) =1a(1) =9a(2) =31a(3) =129a(4) =511a(5) =2049a(6) =8191a(7) =32769a(8) =131071a(9) =524289a(10) =2097151a(11) =8388609a(12) =33554431a(13) =134217729a(14) =536870911a(15) =2147483649a(16) =8589934591a(17) =34359738369a(18) =137438953471a(19) =549755813889