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A078763
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List primes between (2n-1)^2 and (2n)^2.
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2
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2, 3, 11, 13, 29, 31, 53, 59, 61, 83, 89, 97, 127, 131, 137, 139, 173, 179, 181, 191, 193, 227, 229, 233, 239, 241, 251, 293, 307, 311, 313, 317, 367, 373, 379, 383, 389, 397, 443, 449, 457, 461, 463, 467, 479, 541, 547, 557, 563, 569, 571, 631, 641, 643, 647
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OFFSET
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1,1
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COMMENTS
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Primes are on adjacent sides of the Ulam square prime-spiral.
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LINKS
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EXAMPLE
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The 2 primes between 3^2=9 (odd) and 4^2=16 (even) are just a(3)=11 and a(4)=13.
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MAPLE
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2, seq(op(select(isprime, [seq(i, i=(2*n-1)^2..(2*n)^2, 2)])), n=1..20); # Robert Israel, Oct 28 2020
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MATHEMATICA
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f[n_] := Select[Range[(2n - 1)^2, (2n)^2], PrimeQ]; Flatten@Array[f, 13] (* Ray Chandler, May 03 2007 *)
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CROSSREFS
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KEYWORD
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easy,nonn,tabf
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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