a(n) = A135574(n+1) - 2*A135574(n).

Terms

a(0) =0a(1) =3a(2) =-5a(3) =9a(4) =-16a(5) =30a(6) =-63a(7) =129a(8) =-257a(9) =513a(10) =-1024a(11) =2046a(12) =-4095a(13) =8193a(14) =-16385a(15) =32769a(16) =-65536a(17) =131070a(18) =-262143a(19) =524289a(20) =-1048577a(21) =2097153a(22) =-4194304a(23) =8388606a(24) =-16777215a(25) =33554433a(26) =-67108865a(27) =134217729a(28) =-268435456a(29) =536870910