a(1) = 3, a(n) = least k such that concatenation of n copies of k with all previous concatenation gives a prime.

A111473

a(1) = 3, a(n) = least k such that concatenation of n copies of k with all previous concatenation gives a prime.

Terms

    a(0) =3a(1) =1a(2) =1a(3) =11a(4) =113a(5) =7a(6) =23a(7) =41a(8) =37a(9) =141a(10) =733a(11) =241a(12) =3a(13) =791a(14) =781a(15) =701a(16) =239a(17) =441a(18) =2019a(19) =189a(20) =2071a(21) =401a(22) =851a(23) =463a(24) =4421a(25) =497a(26) =2267a(27) =213a(28) =1653a(29) =1683

External references