Primes consisting only of digits 2 and 9 occurring with equal frequency.

Terms

a(0) =29a(1) =22929299a(2) =29229929a(3) =29299229a(4) =29992229a(5) =92922299a(6) =99292229a(7) =2229922999a(8) =2229929929a(9) =2229992299a(10) =2292229999a(11) =2292929299a(12) =2292999229a(13) =2299222999a(14) =2299292929a(15) =2299922929a(16) =2922929929a(17) =2922992299a(18) =2929292299a(19) =2929299229a(20) =2992299229a(21) =2992922299a(22) =2992992229a(23) =2999229229