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A020176 Pseudoprimes to base 48. 1
49, 91, 245, 259, 329, 427, 481, 637, 703, 793, 833, 1105, 1267, 1645, 1729, 1813, 1891, 1921, 2257, 2303, 2305, 2353, 2465, 2701, 2821, 2989, 3367, 3439, 4465, 4753, 5185, 5537, 5551, 5611, 5951, 6533, 6601, 6697, 6721, 7345, 8869, 8911, 9457, 9881, 10021 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 48^(n-1) == 1 (mod n). - Michel Lagneau, Feb 18 2012

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Index entries for sequences related to pseudoprimes

MATHEMATICA

base = 48; 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 *)

Select[Range[11000], CompositeQ[#]&&PowerMod[48, #-1, #]==1&] (* Harvey P. Dale, Feb 26 2022 *)

CROSSREFS

Cf. A001567 (pseudoprimes to base 2).

Sequence in context: A108164 A020158 A084632 * A146064 A224905 A224846

Adjacent sequences: A020173 A020174 A020175 * A020177 A020178 A020179

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified March 25 23:47 EDT 2023. Contains 361529 sequences. (Running on oeis4.)