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A000229 a(n) is the least number such that the n-th prime is the least quadratic nonresidue for a(n) (a(n) is always a prime).
(Formerly M2684 N1074)
6
3, 7, 23, 71, 311, 479, 1559, 5711, 10559, 18191, 31391, 422231, 701399, 366791, 3818929, 9257329, 22000801, 36415991, 48473881, 175244281, 120293879, 427733329, 131486759 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

REFERENCES

H. J. Godwin, On the least quadratic non-residue, Proc. Camb. Phil. Soc., 61 (1965), 671-672.

Hans Sali\'e, \"Uber die kleinste Primzahl, die eine gegebene Primzahl als kleinsten positiven quadratischen Nichtrest hat, Math. Nachr. 29 1965 113-114.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

N. J. A. Sloane, Table of n, a(n) for n=1..38 (from the web page of Tomas Oliveira e Silva)

Tomas Oliveira e Silva, Least primitive root of prime numbers

EXAMPLE

a(2)=7 because the second prime is 3 and 3 is the least quadratic nonresidue for 7, 14, 17, 31, 34, ... and 7 is the least of these.

CROSSREFS

Cf. A025021. For records see A133435.

Differs from A001984, A002223, A045535 at 12th term.

Sequence in context: A140456 A066768 A062241 * A133435 A079061 A191638

Adjacent sequences:  A000226 A000227 A000228 * A000230 A000231 A000232

KEYWORD

nonn,nice

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

Definition corrected by Melvin J. Knight (MELVIN.KNIGHT(AT)ITT.COM), Dec 08 2006

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Last modified February 15 12:25 EST 2012. Contains 205786 sequences.