Number of idempotent 3X3 0..n matrices.

Terms

a(0) =50a(1) =122a(2) =218a(3) =344a(4) =488a(5) =668a(6) =860a(7) =1088a(8) =1334a(9) =1610a(10) =1898a(11) =2234a(12) =2570a(13) =2942a(14) =3338a(15) =3764a(16) =4196a(17) =4676a(18) =5156a(19) =5684a(20) =6224a(21) =6788a(22) =7364a(23) =8000a(24) =8630a(25) =9290a(26) =9974a(27) =10694a(28) =11414a(29) =12194