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A078764 List primes between (2n)^2 and (2n+1)^2. 1
5, 7, 17, 19, 23, 37, 41, 43, 47, 67, 71, 73, 79, 101, 103, 107, 109, 113, 149, 151, 157, 163, 167, 197, 199, 211, 223, 257, 263, 269, 271, 277, 281, 283, 331, 337, 347, 349, 353, 359, 401, 409, 419, 421, 431, 433, 439, 487, 491, 499, 503, 509, 521, 523, 577 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

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

EXAMPLE

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.

MATHEMATICA

f[n_] := Select[Range[(2n)^2, (2n + 1)^2], PrimeQ]; Flatten@Array[f, 12] (*Chandler*)

CROSSREFS

Cf. A014085, A078763.

Sequence in context: A075089 A075305 A140564 * A045318 A040102 A100021

Adjacent sequences:  A078761 A078762 A078763 * A078765 A078766 A078767

KEYWORD

easy,nonn

AUTHOR

Donald S. McDonald (don.mcdonald(AT)paradise.net.nz), Jan 09 2003

EXTENSIONS

Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), May 03 2007

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.