Number of transitive reflexive early confluent binary relations R on n labeled elements where |{y : xRy}| <= 3 for all x.

A210911

Number of transitive reflexive early confluent binary relations R on n labeled elements where |{y : xRy}| <= 3 for all x.

Terms

    a(0) =1a(1) =1a(2) =4a(3) =26a(4) =168a(5) =1416a(6) =13897a(7) =153126a(8) =1893180a(9) =25796852a(10) =383636151a(11) =6177688914a(12) =106969864696

External references