511627domain: NPropertiesPrimalityPrimeyesAppears in sequencesLargest prime substring in 2^n (or 0 if none exist).at n=40A046268Largest prime substring in 4^n (0 if none).at n=20A046270Total number of elements (with multiplicity) in all subsets of [n] having a square element sum.at n=20A377572Prime numbersat n=42419