1831969domain: NPropertiesPrimalityPrimeyesAppears in sequencesa(n) = Sum_{k=0..floor(n/4)} C(n-2*k,2*k) * 3^k.at n=24A098576a(n) = Sum_{k=0..floor(n/2)} binomial(2n-2k,2k) * 3^(n-k).at n=12A108484Prime numbersat n=137312