Reversion of divisor function A000005.

Terms

a(0) =1a(1) =-2a(2) =6a(3) =-23a(4) =102a(5) =-494a(6) =2530a(7) =-13456a(8) =73539a(9) =-410282a(10) =2326674a(11) =-13371039a(12) =77697536a(13) =-455749550a(14) =2694915548a(15) =-16047294182a(16) =96143497559a(17) =-579147165864