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A247881
Numbers of the form x^2 + 13y^2.
2
0, 1, 4, 9, 13, 14, 16, 17, 22, 25, 29, 36, 38, 49, 52, 53, 56, 61, 62, 64, 68, 77, 81, 88, 94, 100, 101, 113, 116, 117, 118, 121, 126, 133, 134, 142, 144, 152, 153, 157, 166, 169, 173, 181, 182, 196, 198, 208, 209, 212, 217, 221, 224, 225, 233, 238, 244, 248, 256, 257, 261, 269
OFFSET
1,3
COMMENTS
Norms of numbers in Z[sqrt(-13)].
CROSSREFS
Cf. A033210 (subsequence of primes).
Sequence in context: A135740 A312870 A312871 * A010412 A033662 A312872
KEYWORD
easy,nonn
AUTHOR
Alonso del Arte, Sep 25 2014
STATUS
approved