Sum of the first n strobogrammatic numbers.

Terms

a(0) =0a(1) =1a(2) =9a(3) =20a(4) =89a(5) =177a(6) =273a(7) =374a(8) =485a(9) =666a(10) =1275a(11) =1894a(12) =2583a(13) =3391a(14) =4209a(15) =5097a(16) =6003a(17) =6919a(18) =7905a(19) =8906a(20) =10017a(21) =11708a(22) =13589a(23) =15550a(24) =21559a(25) =27678a(26) =34377a(27) =41266a(28) =48235a(29) =56243