Numbers that are 3-persistent but not 4-persistent.

Terms

a(0) =1052674893a(1) =1052687493a(2) =1052746893a(3) =1052748693a(4) =1052867493a(5) =1052874693a(6) =1053267489a(7) =1053268749a(8) =1053274869a(9) =1053286749a(10) =1053287469a(11) =1065273489a(12) =1065287349a(13) =1067285493a(14) =1067328549a(15) =1068547293a(16) =1068547329a(17) =1068549273