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A020156 Pseudoprimes to base 28. 1
9, 27, 45, 87, 145, 261, 361, 529, 561, 703, 783, 785, 1105, 1305, 1413, 1431, 1885, 2041, 2413, 2465, 2871, 3201, 3277, 4553, 4699, 5149, 5181, 5365, 7065, 8149, 8321, 8401, 9841, 10027, 10585, 12673, 13333, 13345, 13357, 13833, 14383, 14769, 14981 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Composite numbers n such that 28^(n-1) == 1 (mod n). - Michel Lagneau, Feb 18 2012
LINKS
MATHEMATICA
base = 28; t = {}; n = 1; While[Length[t] < 100, n++; If[! PrimeQ[n] && PowerMod[base, n-1, n] == 1, AppendTo[t, n]]]; t (* T. D. Noe, Feb 21 2012 *)
CROSSREFS
Cf. A001567 (pseudoprimes to base 2).
Sequence in context: A069069 A354815 A031088 * A342869 A287661 A062231
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified April 25 08:27 EDT 2024. Contains 371964 sequences. (Running on oeis4.)