Number of connected regular simple graphs of degree 4 (or quartic graphs) with n nodes.

A006820

Number of connected regular simple graphs of degree 4 (or quartic graphs) with n nodes.

Terms

    a(0) =1a(1) =0a(2) =0a(3) =0a(4) =0a(5) =1a(6) =1a(7) =2a(8) =6a(9) =16a(10) =59a(11) =265a(12) =1544a(13) =10778a(14) =88168a(15) =805491a(16) =8037418a(17) =86221634a(18) =985870522a(19) =11946487647a(20) =152808063181

External references