OFFSET
1,1
REFERENCES
L. E. Dickson, History of the Theory of Numbers, vol. 1, chap. IV.
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..10000
Keller and J. Richstein, Fermat quotients that are divisible by p
EXAMPLE
3 is the smallest prime < A222184(1) = 11 such that 11^2 divides 3^(11-1)-1 = 59048 = 121*488, so a(1) = 3.
MATHEMATICA
L = Select[ Prime[ Range[500]], Product[ PowerMod[ Prime[k], # - 1, #^2] - 1, {k, 1, PrimePi[#] - 1}] == 0 &]; Table[ Min[ Select[ Prime[ Range[ PrimePi[L[[n]]] - 1]], PowerMod[#, L[[n]] - 1, L[[n]]^2] == 1 &]], {n, 1, Length[L]}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Sondow, Feb 12 2013
STATUS
approved