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A133157 Numbers n such that n^2 + n - 41 is prime. 1
8, 15, 20, 21, 26, 29, 36, 45, 48, 59, 68, 69, 75, 78, 98, 99, 108, 111, 113, 120, 129, 134, 138, 140, 143, 161, 168, 185, 188, 189, 210, 213, 215, 216, 218, 224, 230, 231, 234, 251, 255, 260, 266, 273, 278, 279, 281, 290, 294, 299, 306, 308, 314, 320, 329, 356 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

If n=8, then n^2 + n - 41 = 31 (prime)

If n=99, then n^2 + n - 41 = 9859 (prime)

MAPLE

isA133157 := proc(n) isprime(n*(n+1)-41) ; end: for n from 1 to 400 do if isA133157(n) then printf("%d, ", n) ; fi ; od: - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 08 2008

MATHEMATICA

Select[Range[7, 400], PrimeQ[ #^2 + # - 41] &] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Dec 24 2007

CROSSREFS

Cf. A002837.

Sequence in context: A179107 A160524 A161541 * A014544 A122754 A082867

Adjacent sequences:  A133154 A133155 A133156 * A133158 A133159 A133160

KEYWORD

nonn

AUTHOR

Parthasarathy Nambi (PachaNambi(AT)yahoo.com), Dec 17 2007

EXTENSIONS

More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Dec 24 2007

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 08 2008

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Last modified February 17 10:57 EST 2012. Contains 206009 sequences.