A330670 Squares of primes congruent to 1 (mod 30).

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

Offset: 1

Author

Harry E. Neel, Dec 24 2019

Keywords

• nonn

Comments

Sequence lists squares of prime numbers that end in 1 or 9.

Examples

			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.
		

Crossrefs

Intersection of A001248 and A128470.

Programs

Mathematica

Select[Range[360], PrimeQ[#] && Mod[#^2, 30] == 1 &]^2 (* Amiram Eldar, Dec 28 2019 *)

PARI

isok(m) = issquare(m) && isprime(sqrtint(m)) && ((m % 30) == 1); \\ Michel Marcus, Dec 26 2019