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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
OFFSET
1,1
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 A374377 A245807
KEYWORD
nonn,more
AUTHOR
Felix Fröhlich, May 20 2016
STATUS
approved