a(n) is the least positive integer k such that prime(n) + k divides the concatenation of prime(n) - 1 and prime(n).

A385172

a(n) is the least positive integer k such that prime(n) + k divides the concatenation of prime(n) - 1 and prime(n).

Terms

    a(0) =1a(1) =20a(2) =4a(3) =60a(4) =326a(5) =1200a(6) =4a(7) =88a(8) =16a(9) =12a(10) =402a(11) =3600a(12) =408a(13) =4200a(14) =1502a(15) =50a(16) =4a(17) =148a(18) =46a(19) =2286a(20) =966a(21) =7800a(22) =168a(23) =2874a(24) =9600a(25) =82a(26) =102000a(27) =6a(28) =108000a(29) =12344

External references