OFFSET
1,1
COMMENTS
An odd prime p is a term if and only if the Legendre symbol Legendre(q|p) = 1 for all q = 2,3,5,7,11; i.e., each prime q <= 12 is a quadratic residue.
Prime p is a term if and only if all the following conditions are satisfied:
p == +-1 (mod 24)
p == +-1 (mod 10)
p == +-1, +-3, +-9 (mod 28)
p == +-1, +-5, +-7, +-9, +-19 (mod 44)
Prime p is a term if and only if it is congruent to any number in the attached file modulo 9240.
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..10000
Steven Lu, Congruence classes modulo 9240 of the terms
EXAMPLE
479 is a term of this sequence, since Legendre(b|479) = 1 for b = 1, 2, ..., 12.
MATHEMATICA
Select[Prime /@ Range[2000], And @@ Table[KroneckerSymbol[b, #] == 1, {b, Range[12]}] &]
PROG
(PARI) isok(p)={for(i=1, 12, if(kronecker(i, p)<0, return(0))); isprime(p)} \\ Andrew Howroyd, Feb 17 2025
CROSSREFS
KEYWORD
nonn
AUTHOR
Steven Lu, Feb 16 2025
STATUS
approved
