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A330670 Squares of primes congruent to 1 (mod 30). 0
121, 361, 841, 961, 1681, 3481, 3721, 5041, 6241, 7921, 10201, 11881, 17161, 19321, 22201, 22801, 32041, 32761, 36841, 39601, 44521, 52441, 57121, 58081, 63001, 72361, 73441, 78961, 96721, 109561, 121801, 128881, 143641, 151321, 166801, 167281, 175561 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Sequence lists squares of prime numbers that end in 1 or 9.
LINKS
EXAMPLE
Prime 11*11=121 and 19*19=361; 121 and 361 are terms of this sequence.
Prime 13*13=169 and 17*17=289; 169 and 289 are not terms of this sequence.
MATHEMATICA
Select[Range[360], PrimeQ[#] && Mod[#^2, 30] == 1 &]^2 (* Amiram Eldar, Dec 28 2019 *)
PROG
(PARI) isok(m) = issquare(m) && isprime(sqrtint(m)) && ((m % 30) == 1); \\ Michel Marcus, Dec 26 2019
CROSSREFS
Intersection of A001248 and A128470.
Sequence in context: A216166 A208242 A167721 * A253321 A253328 A257035
KEYWORD
nonn
AUTHOR
Harry E. Neel, Dec 24 2019
EXTENSIONS
Deleted an incorrect crossreference. - Harry E. Neel, Jan 22 2020
STATUS
approved

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Last modified July 21 22:27 EDT 2024. Contains 374478 sequences. (Running on oeis4.)