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List primes between (2n)^2 and (2n+1)^2.
1

%I #10 Mar 17 2015 02:15:21

%S 5,7,17,19,23,37,41,43,47,67,71,73,79,101,103,107,109,113,149,151,157,

%T 163,167,197,199,211,223,257,263,269,271,277,281,283,331,337,347,349,

%U 353,359,401,409,419,421,431,433,439,487,491,499,503,509,521,523,577

%N List primes between (2n)^2 and (2n+1)^2.

%C The primes may be on adjacent sides of Ulam square prime-spiral. 7 8 9 / 6 1 2 / 5 4 3/...

%e The 3 primes between 4^2=16 (even) and 5^2=25 (odd) are just a(3)=17, a(4)=19 and a(5)=23.

%t f[n_] := Select[Range[(2n)^2, (2n + 1)^2], PrimeQ];Flatten@Array[f, 12] (* _Ray Chandler_, May 03 2007 *)

%Y Cf. A014085, A078763.

%K easy,nonn

%O 1,1

%A _Donald S. McDonald_, Jan 09 2003

%E Extended by _Ray Chandler_, May 03 2007