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%I #32 Dec 23 2023 06:01:56
%S 2,3,11,13,29,31,53,59,61,83,89,97,127,131,137,139,173,179,181,191,
%T 193,227,229,233,239,241,251,293,307,311,313,317,367,373,379,383,389,
%U 397,443,449,457,461,463,467,479,541,547,557,563,569,571,631,641,643,647
%N List primes between (2n-1)^2 and (2n)^2.
%C Primes are on adjacent sides of the Ulam square prime-spiral.
%H Robert Israel, <a href="/A078763/b078763.txt">Table of n, a(n) for n = 1..10000</a>
%e The 2 primes between 3^2=9 (odd) and 4^2=16 (even) are just a(3)=11 and a(4)=13.
%p 2,seq(op(select(isprime, [seq(i,i=(2*n-1)^2..(2*n)^2,2)])),n=1..20); # _Robert Israel_, Oct 28 2020
%t f[n_] := Select[Range[(2n - 1)^2, (2n)^2], PrimeQ];Flatten@Array[f, 13] (* _Ray Chandler_, May 03 2007 *)
%Y Cf. A014085, A078764.
%K easy,nonn,tabf
%O 1,1
%A _Donald S. McDonald_, Jan 09 2003
%E Extended by _Ray Chandler_, May 03 2007
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