Row sums of the triangle A391318, given by T(n,k) = T(n-1,k) + T(n-1,k-1) + T(n-2,k-1) + 1, with T(0,0) = T(n,-1) = T(n,n+1) = 0.

A391272

Row sums of the triangle A391318, given by T(n,k) = T(n-1,k) + T(n-1,k-1) + T(n-2,k-1) + 1, with T(0,0) = T(n,-1) = T(n,n+1) = 0.

Terms

    a(0) =0a(1) =2a(2) =7a(3) =20a(4) =52a(5) =130a(6) =319a(7) =776a(8) =1880a(9) =4546a(10) =10983a(11) =26524a(12) =64044a(13) =154626a(14) =373311a(15) =901264a(16) =2175856a(17) =5252994a(18) =12681863a(19) =30616740a(20) =73915364a(21) =178447490a(22) =430810367a(23) =1040068248a(24) =2510946888a(25) =6061962050a(26) =14634871015a(27) =35331704108a(28) =85298279260a(29) =205928262658

External references