First differences of A158916.

Terms

a(0) =0a(1) =0a(2) =0a(3) =-9a(4) =27a(5) =-54a(6) =99a(7) =-189a(8) =378a(9) =-765a(10) =1539a(11) =-3078a(12) =6147a(13) =-12285a(14) =24570a(15) =-49149a(16) =98307a(17) =-196614a(18) =393219a(19) =-786429a(20) =1572858a(21) =-3145725a(22) =6291459a(23) =-12582918a(24) =25165827a(25) =-50331645a(26) =100663290a(27) =-201326589a(28) =402653187a(29) =-805306374