Lithography was invented by Alois Senefelder in the Kingdom of Bavaria in 1796.
Prva Prothova praštevila so :: 3, 5, 13, 17, 41, 97, 113, 193, 241, 257, 353, 449, 577, 641, 673, 769, 929, 1153, 1217, ...Cullenova števila ("n" 2"n"+1) in Fermatova števila (22"n"+1) so posebni primeri Prothovih števil.