Even hexagonal pyramidal numbers.

Terms

a(0) =22a(1) =50a(2) =252a(3) =372a(4) =946a(5) =1222a(6) =2360a(7) =2856a(8) =4750a(9) =5530a(10) =8372a(11) =9500a(12) =13482a(13) =15022a(14) =20336a(15) =22352a(16) =29190a(17) =31746a(18) =40300a(19) =43460a(20) =53922a(21) =57750a(22) =70312a(23) =74872a(24) =89726a(25) =95082a(26) =112420a(27) =118636a(28) =138650a(29) =145790