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A347075 Primes of the form p^3 + p^2 + p + 2 where p is prime. 1
41, 157, 401, 2381, 12721, 25261, 81401, 499361, 712981, 1455781, 2705081, 4357481, 7226501, 7684381, 7920401, 12061661, 12703861, 21330941, 22745561, 31955821, 49565921, 54583961, 59015581, 127517041, 237560441, 384769841, 455348741, 506897581, 570410861, 591294481, 866432341, 905167121 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Except for 157, all terms == 1 (mod 20).

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A164939(n)^3 + A164939(n)^2 + A164939(n) + 2.

EXAMPLE

a(3) = 401 because 401 = 7^3 + 7^2 + 7 + 2 and 7 and 401 are prime.

MAPLE

f:= proc(p) local q;

if not isprime(p) then return NULL fi;

q:= p^3+p^2+p+2;

if isprime(q) then return q fi

end proc:

map(f, [seq(i, i=3..1000, 2)]);

CROSSREFS

Cf. A164939.

Sequence in context: A221811 A105100 A141988 * A158602 A245743 A142839

Adjacent sequences:  A347072 A347073 A347074 * A347076 A347077 A347078

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Aug 15 2021

STATUS

approved

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Last modified October 18 23:44 EDT 2021. Contains 348071 sequences. (Running on oeis4.)