Hexagonal numbers (A000384) in which parity of digits alternates.

Terms

a(0) =1a(1) =6a(2) =45a(3) =276a(4) =325a(5) =496a(6) =561a(7) =630a(8) =703a(9) =2145a(10) =2701a(11) =6903a(12) =8385a(13) =10585a(14) =14365a(15) =18721a(16) =25878a(17) =38503a(18) =47278a(19) =74305a(20) =89676a(21) =90525a(22) =107416a(23) =109278a(24) =147696a(25) =149878a(26) =210925a(27) =254541a(28) =303810a(29) =345696