Number of nonnegative integer 3 X 3 matrices with no zero rows or columns and with sum of elements equal to n.

A055005

Number of nonnegative integer 3 X 3 matrices with no zero rows or columns and with sum of elements equal to n.

Terms

    a(0) =1a(1) =0a(2) =0a(3) =6a(4) =63a(5) =306a(6) =1038a(7) =2844a(8) =6750a(9) =14437a(10) =28521a(11) =52911a(12) =93258a(13) =157509a(14) =256581a(15) =405171a(16) =622719a(17) =934542a(18) =1373158a(19) =1979820a(20) =2806281a(21) =3916812a(22) =5390496a(23) =7323822a(24) =9833604a(25) =13060251a(26) =17171415a(27) =22366045a(28) =28878876a(29) =36985383

External references