12-dimensional centered tetrahedral numbers.

Terms

a(0) =1a(1) =14a(2) =105a(3) =560a(4) =2380a(5) =8568a(6) =27132a(7) =77520a(8) =203490a(9) =497420a(10) =1144066a(11) =2496144a(12) =5200300a(13) =10400599a(14) =20058286a(15) =37442055a(16) =67863355a(17) =119757470a(18) =206244507a(19) =347346468a(20) =573088920a(21) =927780270a(22) =1475840380a(23) =2309645534a(24) =3559971156a(25) =5409749996