Octagonal numbers (A000567) in which parity of digits alternates.

Terms

a(0) =1a(1) =8a(2) =21a(3) =65a(4) =96a(5) =341a(6) =3816a(7) =4961a(8) =8321a(9) =8965a(10) =9296a(11) =10325a(12) =12545a(13) =14145a(14) =14981a(15) =16725a(16) =18565a(17) =23056a(18) =27456a(19) =36741a(20) =63656a(21) =65416a(22) =103416a(23) =105656a(24) =169456a(25) =181056a(26) =210145a(27) =216545a(28) =232965a(29) =236321