2429411domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrime numbers P such that 10^(n+d+1) + P*10^n + 1 is prime for n=1 to 5 with d = number of digits of P.at n=6A180949Prime numbers that have a dodecagonal (12 sides) Voronoi cell in the Voronoi diagram of the Ulam prime spiral.at n=11A257749Prime numbersat n=178292