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A272933
Numbers of the form x^2 + 12*y^2.
1
0, 1, 4, 9, 12, 13, 16, 21, 25, 28, 36, 37, 48, 49, 52, 57, 61, 64, 73, 76, 81, 84, 93, 97, 100, 108, 109, 112, 117, 121, 124, 129, 133, 144, 148, 156, 157, 169, 172, 181, 189, 192, 193, 196, 201, 208, 217, 225, 228, 229, 237, 241, 244, 252, 256, 268, 273, 277
OFFSET
1,3
COMMENTS
x^2 + 12*y^2 has discriminant -48.
All terms are congruent to {0, 1, 4, 9, 12, 13, 16, 21, 25, 28} (mod 36).
Norms of numbers in Z[sqrt(-12)].
PROG
(Magma) [n: n in [0..277] | NormEquation(12, n) eq true];
CROSSREFS
Cf. A003136. A068228 gives the primes.
Sequence in context: A312848 A010413 A112652 * A367929 A243650 A140399
KEYWORD
nonn,easy
AUTHOR
STATUS
approved