Number of distinct values of the sum of a*b+a*c+b*c over 2 sets of three a,b,c 0..n integers.

Terms

a(0) =6a(1) =20a(2) =44a(3) =78a(4) =123a(5) =178a(6) =244a(7) =322a(8) =411a(9) =510a(10) =622a(11) =743a(12) =876a(13) =1022a(14) =1178a(15) =1345a(16) =1525a(17) =1715a(18) =1915a(19) =2129a(20) =2354a(21) =2587a(22) =2835a(23) =3094a(24) =3364a(25) =3646a(26) =3939a(27) =4245a(28) =4562a(29) =4888