Pell numbers A000129 with 0 instead of last digit.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =10a(5) =20a(6) =70a(7) =160a(8) =400a(9) =980a(10) =2370a(11) =5740a(12) =13860a(13) =33460a(14) =80780a(15) =195020a(16) =470830a(17) =1136680a(18) =2744210a(19) =6625100a(20) =15994420a(21) =38613960