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%I #23 Aug 17 2021 02:14:43
%S 41,157,401,2381,12721,25261,81401,499361,712981,1455781,2705081,
%T 4357481,7226501,7684381,7920401,12061661,12703861,21330941,22745561,
%U 31955821,49565921,54583961,59015581,127517041,237560441,384769841,455348741,506897581,570410861,591294481,866432341,905167121
%N Primes of the form p^3 + p^2 + p + 2 where p is prime.
%C Except for 157, all terms == 1 (mod 20).
%H Robert Israel, <a href="/A347075/b347075.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A164939(n)^3 + A164939(n)^2 + A164939(n) + 2.
%e a(3) = 401 because 401 = 7^3 + 7^2 + 7 + 2 and 7 and 401 are prime.
%p f:= proc(p) local q;
%p if not isprime(p) then return NULL fi;
%p q:= p^3+p^2+p+2;
%p if isprime(q) then return q fi
%p end proc:
%p map(f, [seq(i,i=3..1000,2)]);
%Y Cf. A164939.
%K nonn
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Aug 15 2021
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