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A273340 Smallest base b such that A273339(b) = A002808(n), i.e., smallest base b > 1 such that the n-th composite number is the smallest "non-Wieferich pseudoprime" to base b. 1
2, 17, 145, 577, 5185 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..5.

PROG

(PARI) composite(n) = my(i=0, c=2); while(1, if(!ispseudoprime(c), i++); if(i==n, return(c)); c++)

a273339(n) = forcomposite(c=1, , if(Mod(n, c^2)^(c-1)!=1, return(c)))

a(n) = my(b=2, c=composite(n)); while(a273339(b)!=c, b++); b

CROSSREFS

Cf. A273339.

Sequence in context: A037636 A163066 A110815 * A074624 A245807 A295946

Adjacent sequences:  A273337 A273338 A273339 * A273341 A273342 A273343

KEYWORD

nonn,more

AUTHOR

Felix Fröhlich, May 20 2016

STATUS

approved

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Last modified May 26 17:17 EDT 2019. Contains 323597 sequences. (Running on oeis4.)