5th diagonal of triangle in A059317.

Terms

a(0) =0a(1) =0a(2) =0a(3) =1a(4) =8a(5) =29a(6) =72a(7) =146a(8) =261a(9) =428a(10) =659a(11) =967a(12) =1366a(13) =1871a(14) =2498a(15) =3264a(16) =4187a(17) =5286a(18) =6581a(19) =8093a(20) =9844a(21) =11857a(22) =14156a(23) =16766a(24) =19713a(25) =23024a(26) =26727a(27) =30851a(28) =35426a(29) =40483