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%I #8 May 12 2017 10:25:17
%S 12207031,2141993519227,178250690949465223,2346320474383711003267,
%T 398341412240537151131351,79545183674814239059370551,
%U 494424256962371823779424877,8271964541879648991904246901,32142180034067960734115528951,91264002187709396686868598317
%N Primes of the form p^10 + p^9 + p^8 + p^7 + p^6 + p^5 + p^4 + p^3 + p^2 + p + 1 when p is prime.
%e Prime number 12207031 = Sum_{i=0..10} 5^i is the first in the sequence since 23 divides 88573 = Sum_{i=0..10} 3^i as well as 2047 = Sum_{i=0..10} 2^i.
%t a286301[n_] := Select[Map[(Prime[#]^11-1)/(Prime[#]-1)&, Range[n]], PrimeQ]
%t a286301[150] (* data *)
%Y Subsequence of A060885, A162861 and A193574.
%Y Cf. A162862, A198244, A240693.
%K nonn
%O 1,1
%A _Hartmut F. W. Hoft_, May 05 2017