384941domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumber of distinct prime factors of the n-th odd Catalan number, A038003(n).at n=21A119861Number of nX3 nonnegative integer arrays with upper left 0 and lower right n+3-4 and value increasing by 0 or 1 with every step right or down.at n=19A252871Prime numbersat n=32679