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A374914
Primes p == 2, 3 (mod 4) with 2*p+1 prime.
2
2, 3, 11, 23, 83, 131, 179, 191, 239, 251, 359, 419, 431, 443, 491, 659, 683, 719, 743, 911, 1019, 1031, 1103, 1223, 1439, 1451, 1499, 1511, 1559, 1583, 1811, 1931, 2003, 2039, 2063, 2339, 2351, 2399, 2459, 2543, 2699, 2819, 2903, 2939, 2963, 3023, 3299, 3359, 3491
OFFSET
1,1
COMMENTS
2 together with Lucasian primes (A002515).
Primes p such that p^(p + 1) == p + 1 (mod 2*p + 1).
FORMULA
a(n) >> n log^2 n. - Charles R Greathouse IV, Jul 25 2024
EXAMPLE
2 is in this sequence because 2^(2 + 1) = 8 and 8 = 3 (mod 2*2 + 1) where 2 prime.
MATHEMATICA
Select[Prime[Range[490]], Mod[#^(#+1), 2#+1]==#+1 &] (* Stefano Spezia, Jul 23 2024 *)
PROG
(PARI) list(lim)=my(v=List([2])); forprimestep(p=3, lim\1, 4, if(isprime(2*p+1), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Jul 25 2024
CROSSREFS
Supersequence of A002515. Subsequence of A374913.
Cf. A374912.
Sequence in context: A292817 A292112 A363141 * A065849 A136402 A137811
KEYWORD
nonn,easy
AUTHOR
STATUS
approved