A087691 Squares of primes of the form 4*k+3.

9, 49, 121, 361, 529, 961, 1849, 2209, 3481, 4489, 5041, 6241, 6889, 10609, 11449, 16129, 17161, 19321, 22801, 26569, 27889, 32041, 36481, 39601, 44521, 49729, 51529, 57121, 63001, 69169, 73441, 80089, 94249, 96721, 109561, 120409, 128881

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..10000

Formula

a(n) = A002145(n)^2.

a(n) ~ 4n^2 * (log n)^2. - Charles R Greathouse IV, Sep 20 2016

From Amiram Eldar, Dec 02 2022: (Start)

Product_{n>=1} (1 + 1/a(n)) = A243381.

Product_{n>=1} (1 - 1/a(n)) = A243379. (End)

Mathematica

Select[4*Range[0, 100]+3, PrimeQ]^2 (* Harvey P. Dale, Sep 10 2012 *)

Prog

(PARI) p4np3(n)= forprime(x=3, n, if(x%4==3, y=x*x; print1(y, ", ")));

Crossrefs

Cf. A002145, A243379, A243381.

Sequence in context: A138998 A339125 A016838 * A014730 A212503 A295019

Adjacent sequences: A087688 A087689 A087690 * A087692 A087693 A087694

Keyword

nonn,easy

Author

Cino Hilliard, Sep 27 2003

Extensions

More terms from Ray Chandler, Oct 26 2003

Status

approved