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A020190 Pseudoprimes to base 62. 1
9, 21, 45, 63, 91, 105, 183, 231, 305, 361, 427, 549, 561, 671, 679, 703, 793, 861, 1105, 1261, 1281, 1541, 1729, 2121, 2465, 2501, 2745, 2871, 3367, 3439, 3843, 3845, 4141, 4187, 4577, 5185, 5307, 5551, 5565, 5901, 5917, 6161, 6405, 6533, 6601, 6697, 6849 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Composite numbers n such that 62^(n-1) == 1 (mod n). [From 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 = 62; 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[7000], CompositeQ[#]&&PowerMod[62, #-1, #]==1&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 20 2019 *)

CROSSREFS

Cf. A001567 (pseudoprimes to base 2).

Sequence in context: A154862 A020137 A231570 * A225507 A135187 A246318

Adjacent sequences:  A020187 A020188 A020189 * A020191 A020192 A020193

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified December 6 22:25 EST 2021. Contains 349567 sequences. (Running on oeis4.)