151536domain: NAppears in sequencesSum{T(i,n-i): i=0,1,...,n}, array T as in A047150.at n=18A047151a(n) = Sum_{j=0..floor(n/2)} T(2*j + q), where T(n) are generalized tribonacci numbers (A001644) and q = n - 2*floor(n/2).at n=19A074475a(n) = (1/4)*A291732(n).at n=12A291733