Number of labeled 2-regular digraphs with n nodes.
A007107
Number of labeled 2-regular digraphs with n nodes.
Terms
- a(0) =1a(1) =0a(2) =0a(3) =1a(4) =9a(5) =216a(6) =7570a(7) =357435a(8) =22040361a(9) =1721632024a(10) =166261966956
External references
- oeis: A007107