login
Numbers n such that the concatenation of consecutive increasing numbers beginning with prime(n) and ending with prime(n+1) is prime; or n such that A111875(n) is prime.
0

%I #4 Apr 03 2023 10:36:10

%S 1,37,58,119,130,195,292,419,453,464,561,617,618,652,679,720,762,787,

%T 827,830,945,1034,1090,1139,1191,1200,1344,1383,1386,1451,1496,1519,

%U 1774,1783,1820,1822,1911,1966,1973,2018,2128,2219,2247,2378,2566,2644

%N Numbers n such that the concatenation of consecutive increasing numbers beginning with prime(n) and ending with prime(n+1) is prime; or n such that A111875(n) is prime.

%C Honaker's prime curiosity corresponds to a(2)=37. Concatenating all the increasing numbers from prime(1473480)=23428439 to prime(1473481)=23428523 produces a 680-digit prime (certified).

%H G. L. Honaker, Jr., <a href="https://t5k.org/curios/page.php/157158159160161162163.html">Prime Curios</a>

%e a(3)=58 because prime(58)=271 and prime(59)=277 and 271272273274275276277

%e is prime.

%K easy,nonn,base

%O 1,2

%A _Jason Earls_, Aug 18 2005