login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A014556 Euler's "Lucky" numbers: n such that m^2-m+n is prime for m=0..n-1. 8
2, 3, 5, 11, 17, 41 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Same as n such that 4n-1 is a Heegner number 1,2,3,7,11,19,43,67,163 (see A003173 and Conway and Guy's book).

REFERENCES

J. H. Conway and R. K. Guy, The Book of Numbers, Copernicus Press, NY, 1996, p. 225.

J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 41, p. 16, Ellipses, Paris 2008.

F. Le Lionnais, Les Nombres Remarquables. Paris: Hermann, pp. 88 and 144, 1983.

LINKS

Eric Weisstein's World of Mathematics, Lucky Number of Euler

Eric Weisstein's World of Mathematics, Prime-Generating Polynomial

FORMULA

a(n)=(A003173(n+3)+1)/4. [From M. F. Hasler (www.univ-ag.fr/~mhasler), Nov 03 2008]

CROSSREFS

Cf. A000926, A003173, A092749.

Cf. A117530, A117531.

Sequence in context: A079370 A014210 A203074 * A062737 A085613 A082605

Adjacent sequences:  A014553 A014554 A014555 * A014557 A014558 A014559

KEYWORD

nonn,fini,full,nice

AUTHOR

Eric Weisstein (eric(AT)weisstein.com)

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 10 12:10 EST 2012. Contains 205227 sequences.