1851851domain: NPropertiesPrimalityPrimeyesAppears in sequencesSmallest prime formed by a substring of the decimal digits of 1/n beginning with the first (nonzero) digit after the decimal point, or 0 if no such prime exists.at n=53A088324Primes p such that (2*p + 1)*(8*p + 1)*(18*p + 1) divides 2^p - 1.at n=7A231918Prime numbersat n=138670