369944

Appears in sequences

• Triangle read by rows: T(n,k) is the number of indecomposable (connected) permutations of {1,2,...,n} having genus k (see first comment for definition of genus).at n=49A185209
• Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,2,1,0,4 for x=0,1,2,3,4.at n=12A196976