Numbers n with the property that the symmetric representation of sigma(n) has four parts, each of width one and two regions meet at the center of the Dyck path.

A264104

Numbers n with the property that the symmetric representation of sigma(n) has four parts, each of width one and two regions meet at the center of the Dyck path.

Terms

    a(0) =21a(1) =55a(2) =253a(3) =406a(4) =1081a(5) =1378a(6) =1711a(7) =3403a(8) =3916a(9) =5671a(10) =9316a(11) =11026a(12) =13861a(13) =14878a(14) =15931a(15) =25651a(16) =27028a(17) =34453a(18) =36046a(19) =42778a(20) =50086a(21) =60031a(22) =64261a(23) =73153a(24) =75466a(25) =108811a(26) =114481a(27) =126253a(28) =129286a(29) =154846

External references