Primes of the form: concatenation n with n-th composite integer.

Terms

a(0) =4057a(1) =4463a(2) =4969a(3) =5881a(4) =6691a(5) =86117a(6) =90121a(7) =129169a(8) =131171a(9) =136177a(10) =160207a(11) =162209a(12) =169217a(13) =193247a(14) =225287a(15) =252319a(16) =265333a(17) =272341a(18) =280351a(19) =288361a(20) =297371a(21) =327407a(22) =346429a(23) =355441a(24) =388481a(25) =410507a(26) =429529a(27) =451553a(28) =456559a(29) =474581