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A211456
Smallest base b for which A181780(n) is a Fermat pseudoprime.
6
4, 8, 7, 9, 10, 6, 14, 8, 18, 16, 9, 21, 20, 8, 8, 25, 22, 11, 26, 45, 34, 4, 28, 3, 32, 39, 10, 8, 38, 65, 24, 8, 50, 3, 40, 5, 57, 44, 61, 8, 26, 46, 12, 12, 50, 121, 8, 23, 61, 52, 22, 23, 19, 37, 49, 24, 49, 58, 62, 6, 97, 67, 55, 11, 14, 165, 68, 57, 9
OFFSET
1,1
COMMENTS
That is, the smallest b for which b^(s-1) = 1 (mod s), where s is in A181780.
MATHEMATICA
t = {}; n = 1; While[Length[t] < 100, n++; If[! PrimeQ[n], s = Select[Range[2, n-2], PowerMod[#, n-1, n] == 1 &]; If[s != {}, AppendTo[t, {n, Length[s], s}]]]]; First/@Transpose[t][[3]]
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Apr 13 2012
STATUS
approved