Indices of primes in the sequence defined by A(0) = 41, A(n) = 10*A(n-1) + 21 for n > 0.

Terms

a(0) =0a(1) =1a(2) =3a(3) =6a(4) =9a(5) =11a(6) =19a(7) =23a(8) =29a(9) =41a(10) =61a(11) =187a(12) =303a(13) =339a(14) =714a(15) =803a(16) =1039a(17) =1886a(18) =2078a(19) =2119a(20) =2259a(21) =2422a(22) =3318a(23) =5597a(24) =6071a(25) =22047a(26) =25712a(27) =28643a(28) =43352