A244032 Positive numbers n such that there exists a positive number m != n such that x^2+ny^2 and x^2+my^2 represent the same odd primes.

1, 4, 8, 9, 12, 16, 24, 45, 48, 72, 80, 120, 240

Offset: 1

Author

N. J. A. Sloane, Jun 22 2014

Keywords

• nonn

Comments

There are no other terms for which both n and m are < 100000.

Examples

			For example, 9 and 12 are members because the odd primes (in fact all the primes) represented by x^2+9y^2 and x^2+12y^2 are the same - see A068228.
		

Links

• William C. Jagy and Irving Kaplansky, Positive definite binary quadratic forms that represent the same primes [Cached copy]
• N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)

Crossrefs

Cf. A068228.