545270

Appears in sequences

• Number of noncrossing connected graphs on n nodes on a circle having no triangular faces.at n=8A045743
• Triangle read by rows: T(n,k) (n >= 2, k >= 0) is the number of non-crossing connected graphs on n nodes on a circle, having k triangles. Rows are indexed 2,3,4,...; columns are indexed 0,1,2,....at n=36A089435
• Expansion of (1/x) * Series_Reversion( x / (1 + x^2 / (1 - x)^4) ).at n=12A389247