Number of cusps in a class of degree-3n complex algebraic surfaces.

Terms

a(0) =3a(1) =30a(2) =127a(3) =301a(4) =647a(5) =1100a(6) =1851a(7) =2715a(8) =4027a(9) =5434a(10) =7463a(11) =9545a(12) =12447a(13) =15336a(14) =19267a(15) =23095a(16) =28211a(17) =33110a(18) =39567a(19) =45669a(20) =53623a(21) =61060a(22) =70667a(23) =79571a(24) =90987a(25) =101490a(26) =114871a(27) =127105a(28) =142607a(29) =156704