Any two consecutive digits in the sequence sum up to a prime.

Terms

a(0) =1a(1) =2a(2) =3a(3) =4a(4) =7a(5) =41a(6) =43a(7) =47a(8) =49a(9) =83a(10) =85a(11) =89a(12) =202a(13) =302a(14) =303a(15) =411a(16) =412a(17) =502a(18) =503a(19) =830a(20) =2020a(21) =2021a(22) =2023a(23) =2025a(24) =2029a(25) =2030a(26) =2032a(27) =3020a(28) =3021a(29) =4111