Numbers k such that 10^k+sigma(k^2) is prime.

Terms

a(0) =1a(1) =2a(2) =3a(3) =8a(4) =13a(5) =15a(6) =19a(7) =20a(8) =41a(9) =47a(10) =50a(11) =76a(12) =100a(13) =162a(14) =204a(15) =310a(16) =318a(17) =536a(18) =2502a(19) =4016a(20) =5612a(21) =5849a(22) =52753a(23) =64843