157392

Appears in sequences

• G.f. satisfies A(x) = 1 + Sum_{n>=0} (x*A(x))^(2^n).at n=13A075864
• Number of 4-cycles in the n-Keller graph.at n=2A300842
• a(n) = Sum_{-n<i<n, -n<j<n, gcd{i,j}=3} (n-|i|)*(n-|j|).at n=38A331774