7684661domain: NPropertiesPrimalityPrimeyesAppears in sequencesa(n) = 5*a(n-1) - 2*a(n-2), with a(0)=2, a(1)=9.at n=10A020698Expansion of (1+2*x-x^3) / (1-5*x^2+2*x^4).at n=21A384611Prime numbersat n=519918