Dodecahedral surface numbers: a(0)=0, a(1)=1, a(2)=20, thereafter 2*((3*n-7)^2 + 21).

Terms

a(0) =0a(1) =1a(2) =20a(3) =50a(4) =92a(5) =170a(6) =284a(7) =434a(8) =620a(9) =842a(10) =1100a(11) =1394a(12) =1724a(13) =2090a(14) =2492a(15) =2930a(16) =3404a(17) =3914a(18) =4460a(19) =5042a(20) =5660a(21) =6314a(22) =7004a(23) =7730a(24) =8492a(25) =9290a(26) =10124a(27) =10994a(28) =11900a(29) =12842