33385domain: NAppears in sequencesPisot sequence E(10,21), a(n) = floor( a(n-1)^2/a(n-2)+1/2 ).at n=11A014007Numbers k such that (phi(k-2) + phi(k+2))/2 = phi(k); 2-phi/balanced numbers.at n=26A099633G.f. satisfies: A(x) = Sum_{n>=0} x^n * A(x)^(n^2).at n=8A107595