

A060397


Smallest prime that divides k^2 + k + 2n + 1 for k = 0,1,2,....


2



3, 3, 5, 3, 3, 11, 3, 3, 17, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 3, 41, 3, 3, 7, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 3, 7, 3, 3, 7, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 3, 11, 3, 3, 7, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 3, 7, 3, 3, 11, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 3, 7, 3, 3, 11, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 3, 7, 3, 3, 7, 3, 3
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OFFSET

0,1


COMMENTS

Bisection of A060395.


LINKS

T. D. Noe, Table of n, a(n) for n = 0..10000
C. Rivera, www.primepuzzles.net, Conjecture 17


FORMULA

a(n)=3 if n is equal to 0 or 1 mod 3.


EXAMPLE

To obtain a(3), note that x^2+x+7 takes the values 7,9,13,19,... for k=0,1,2,... and the smallest prime dividing these numbers is 3.


CROSSREFS

Cf. A060380, A060392A060398. A060398 gives values of k.
Sequence in context: A235649 A113965 A162277 * A014780 A216199 A073081
Adjacent sequences: A060394 A060395 A060396 * A060398 A060399 A060400


KEYWORD

nonn,easy,nice


AUTHOR

N. J. A. Sloane, Apr 04 2001


EXTENSIONS

More terms from Matthew Conroy, Apr 18 2001


STATUS

approved



