Number of nonzero palindromes of length n containing the digit '0'.

Terms

a(0) =0a(1) =0a(2) =9a(3) =9a(4) =171a(5) =171a(6) =2439a(7) =2439a(8) =30951a(9) =30951a(10) =368559a(11) =368559a(12) =4217031a(13) =4217031a(14) =46953279a(15) =46953279a(16) =512579511a(17) =512579511a(18) =5513215599a(19) =5513215599a(20) =58618940391a(21) =58618940391a(22) =617570463519a(23) =617570463519