Concatenation of n in base 10 down up to base 2 is prime, all numbers are interpreted as decimals.

Terms

a(0) =21a(1) =117a(2) =241a(3) =283a(4) =389a(5) =517a(6) =547a(7) =627a(8) =1219a(9) =1223a(10) =1247a(11) =1285a(12) =1287a(13) =1323a(14) =1467a(15) =1505a(16) =1591a(17) =1599a(18) =1689a(19) =1713a(20) =1817a(21) =1961a(22) =2203a(23) =2309a(24) =2377a(25) =2607a(26) =2837a(27) =2847a(28) =2899a(29) =2911