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A056908 Numbers n such that 36n^2+36n+13 is prime. 2
0, 2, 4, 5, 7, 9, 14, 19, 22, 24, 29, 30, 34, 40, 42, 44, 50, 59, 62, 70, 72, 74, 75, 79, 80, 82, 84, 95, 102, 110, 119, 125, 132, 135, 139, 149, 150, 157, 160, 165, 172, 180, 197, 199, 200, 209, 210, 212, 224, 225, 227, 229, 230, 232, 235, 240, 244, 249 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

36n^2+36n+13=(6n+3)^2+4 which is 4 more than a square.

EXAMPLE

a(2)=4 since 36*4^2+36*4+13=733 which is prime (as well as being four more than a square)

CROSSREFS

This sequence and formula, together with A056907 and its formula, generate all primes of the form k^2+4, i.e. A005473. Cf. A056900, A056902, A056904, A056906.

Sequence in context: A193494 A161832 A078404 * A060565 A133254 A080725

Adjacent sequences:  A056905 A056906 A056907 * A056909 A056910 A056911

KEYWORD

nonn

AUTHOR

Henry Bottomley (se16(AT)btinternet.com), Jul 07 2000

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Last modified February 16 15:27 EST 2012. Contains 205930 sequences.