8344332288domain: NAppears in sequencesa(n) = Sum_{k=0..2n} (k+1) * A026519(n, k).at n=22A027266a(n) = Sum_{k=0..2n} (k+1)*T(n,k), where T is given by A026536.at n=22A027271a(n) = (2*n + 1)*6^n.at n=11A199299