

A121521


Least positive k such that (10^n+1)^n + k is prime.


2



1, 2, 10, 2, 16, 12, 220, 60, 112, 222, 112, 30, 618, 348, 156, 248, 10, 290, 256, 2346, 118, 570, 738, 348, 1356, 4352, 1402, 470, 736, 300, 10428, 4962, 4882, 1382, 580, 948, 5112, 776, 358, 7158, 1458, 21056, 318, 4376, 2472, 2738, 9178, 2538, 10518, 4908, 11316
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OFFSET

0,2


COMMENTS

The 100th term is 16456; ((10^100+1)^100)+16456 is a probable prime with 10001 digits.


LINKS



MATHEMATICA

lpk[n_]:=Module[{c=(10^n+1)^n}, NextPrime[c]c]; Array[lpk, 40, 0] (* Harvey P. Dale, Sep 04 2017 *)


PROG

(PARI) a(n) = nextprime(1+m=(10^n+1)^n)  m; \\ Jinyuan Wang, Jun 07 2020


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



