Concatenation of n-th prime and n-th nonprime.

Terms

a(0) =21a(1) =34a(2) =56a(3) =78a(4) =119a(5) =1310a(6) =1712a(7) =1914a(8) =2315a(9) =2916a(10) =3118a(11) =3720a(12) =4121a(13) =4322a(14) =4724a(15) =5325a(16) =5926a(17) =6127a(18) =6728a(19) =7130a(20) =7332a(21) =7933a(22) =8334a(23) =8935a(24) =9736a(25) =10138a(26) =10339a(27) =10740a(28) =10942a(29) =11344