A007324 - OEIS

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A007324

Least number for which Solovay-Strassen primality test on bases < prime(n) fails.
(Formerly M5443)

9, 561, 1729, 1729, 399001, 399001, 1857241, 1857241, 6189121, 14469841, 14469841, 14469841

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

REFERENCES

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

LINKS

Table of n, a(n) for n=1..12.

Wikipedia, Solovay-Strassen primality test

PROG

(PARI) a(n) = my(b, p=factorback(primes(n-1))); forcomposite(k=9, oo, if(gcd(k, p)==1, b=2; while(Mod(b, k)^(k\2) == kronecker(b, k), b++); if(b>=prime(n), return(k)))); \\ Jinyuan Wang, Jun 04 2022

CROSSREFS

Cf. A083876, A271221, A329726.

Sequence in context: A357229 A267548 A326614 * A354692 A373882 A347844

Adjacent sequences: A007321 A007322 A007323 * A007325 A007326 A007327

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Eric Bach (bach(AT)cs.wisc.edu)

EXTENSIONS

Offset changed to 1 and a(1) corrected by Jinyuan Wang, Jun 04 2022

STATUS

approved