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.

2, 17, 145, 577, 5185

Offset: 1

Author

Felix Fröhlich, May 20 2016

Keywords

• nonn
• more

Crossrefs

Cf. A273339.

Programs

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