A102497 Primes of the concatenated form 1nn1 where n is an integer >=0.
112121, 113131, 115151, 119191, 127271, 131311, 134341, 136361, 140401, 142421, 145451, 149491, 157571, 158581, 161611, 169691, 170701, 172721, 178781, 182821, 187871, 190901, 191911, 196961, 197971, 1100010001, 1100210021, 1101710171
Offset: 1
Examples
112121 is prime and is of the form 1nn1 for n=12. 1100010001 is prime and is of the form 1nn1 for n=1000.