Number of not necessarily connected 4-regular simple graphs on n vertices with girth exactly 3.

A185143

Number of not necessarily connected 4-regular simple graphs on n vertices with girth exactly 3.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =1a(6) =1a(7) =2a(8) =5a(9) =16a(10) =58a(11) =264a(12) =1535a(13) =10755a(14) =87973a(15) =803973a(16) =8020967a(17) =86029760a(18) =983431053a(19) =11913921910a(20) =152352965278

External references