43952

Appears in sequences

• Number of (n+1) X 3 binary arrays with every 2 X 2 subblock commuting with each of its horizontal and vertical 2 X 2 subblock neighbors.at n=18A186455
• E.g.f. satisfies: A(x) = x + tan( A(x) )^2 with A(0)=0.at n=5A201561
• Number of integer compositions of n that have only one part or whose consecutive parts are coprime and the last and first part are also coprime.at n=18A318748