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A027864
Primes of the form k^2 + (k+1)^2 + (k+2)^2 = 3*(k+1)^2+2.
11
5, 29, 149, 509, 677, 1877, 3677, 8429, 9749, 11909, 13469, 17789, 22709, 27077, 28229, 45389, 46877, 53069, 70229, 72077, 81677, 100469, 102677, 114077, 128549, 141269, 154589, 180077, 192029, 195077, 207509, 223589, 230189, 261077, 312989, 340709
OFFSET
1,1
COMMENTS
Same as A257163 without its first term. - Jonathan Sondow, Oct 24 2015
The domain of k is not explicit. If the domain is all integers then the sequence A257163 is produced. In this sequence domain is all nonnegative integers. - Michael Somos, Oct 24 2015
LINKS
MATHEMATICA
Select[Table[3n^2+6n+5, {n, 0, 400}], PrimeQ] (* Harvey P. Dale, Oct 22 2016 *)
Select[Table[Total[Range[n, n+2]^2], {n, 0, 500}], PrimeQ] (* Harvey P. Dale, May 23 2021 *)
PROG
(PARI) select(isprime, vector(100, n, 3*n^2+2)) \\ Charles R Greathouse IV, Apr 17 2015
(Python)
from sympy import isprime
print(list(filter(isprime, (3*k**2+6*k+5 for k in range(350))))) # Michael S. Branicky, May 29 2021
CROSSREFS
Sequence in context: A060963 A107002 A339957 * A272839 A272921 A198764
KEYWORD
nonn,easy
EXTENSIONS
More terms from Claudio Meller, Jun 25 2009
STATUS
approved