1298053domain: NPropertiesPrimalityPrimeyesAppears in sequencesExpansion of the exponential series exp( x * T(x) ) = exp( x / sqrt(1 - 2*x - 3*x^2) ), where T(x) is the ordinary generating series of the central trinomial coefficients (A002426).at n=7A080896Prime numbersat n=99892