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%I #25 Jul 10 2015 20:14:46
%S 7,17,73,97,193,241,313,337,409,457,577,1009,1129,1201,1249,1321,1489,
%T 1657,1801,1873,2017,2137,2377,2521,2689,2833,2857,3049,3169,3217,
%U 3361,3529,3697,3769,3889,4057,4177,4441,4513,4561,4657,5209,5449,5569,5689,5857
%N Primes of the form x^2 + y^2 - 1, where x and y are primes.
%C Unlike primes of the form x^2+y^2 (A045637) which can be redefined as x^2+4, and primes of the form x^2+y^2+1 (A182475) which can be redefined as primes of the form x^2+10, this sequence appears to have no one-variable analog. In the preceding, x and y are prime.
%H Christian N. K. Anderson, <a href="/A217717/b217717.txt">Table of n, a(n) for n = 1..10000</a>
%e 457 is in the sequence because it is a prime number, and 457 = 13^2 + 17^2 - 1.
%t mx = 25; Union[Select[Flatten[Table[Prime[a]^2 + Prime[b]^2 - 1, {a, mx}, {b, a, mx}]], # < Prime[mx]^2 && PrimeQ[#] &]] (* _T. D. Noe_, Mar 29 2013 *)
%Y Cf. A045637 (primes of the form p^2+4, where p is prime).
%Y Cf. A182475 (primes of the form p^2+10, where p is prime).
%K nonn
%O 1,1
%A _Kevin L. Schwartz_ and _Christian N. K. Anderson_, Mar 21 2013
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