a(n+1) = 2*a(n-2) + a(n-1), with a(0) = 3, a(1) = 0, and a(2) = 2.

Terms

a(0) =3a(1) =0a(2) =2a(3) =6a(4) =2a(5) =10a(6) =14a(7) =14a(8) =34a(9) =42a(10) =62a(11) =110a(12) =146a(13) =234a(14) =366a(15) =526a(16) =834a(17) =1258a(18) =1886a(19) =2926a(20) =4402a(21) =6698a(22) =10254a(23) =15502a(24) =23650a(25) =36010a(26) =54654a(27) =83310a(28) =126674a(29) =192618