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A153581 Pseudoprimes to bases 2,3,5 and 7 which are not Carmichael numbers (A002997). 4
721801, 8646121, 10403641, 22885129, 36307981, 42702661, 46094401, 48064021, 52204237, 79398901, 80918281, 81954133, 114329881, 116151661, 143168581, 170782921, 188985961, 217145881, 220531501, 282707461, 299671921, 303373801, 326695141, 353815801, 361307521 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Terms congruent to 5 (mod 6): 468950021, 493108481, 659846021, 5936122901, 8144063621, ... - Robert G. Wilson v, Sep 03 2014

Terms not congruent to 1 (mod 12): 468950021, 493108481, 643767931, 659846021, 773131927, 5779230451, 5936122901, 7294056727, 8144063621, 9671001451, ... - Robert G. Wilson v, Sep 03 2014

LINKS

Robert G. Wilson v, Table of n, a(n) for n = 1..125

MATHEMATICA

fQ[n_] := ! PrimeQ[n] && PowerMod[2, n - 1, n] == 1 && PowerMod[3, n - 1, n] == 1 && PowerMod[5, n - 1, n] == 1 && PowerMod[7, n - 1, n] == 1 && Mod[n, CarmichaelLambda[n]] != 1; Select[ Range[ 365000000], fQ] (* Ray Chandler; corrected by Robert G. Wilson v, Sep 01 2014 *)

CROSSREFS

Cf. A002997, A083737, A122780, A153508, A153513, A153514, A153515, A153519, A153580.

Sequence in context: A015346 A190932 A153580 * A100383 A250153 A252324

Adjacent sequences:  A153578 A153579 A153580 * A153582 A153583 A153584

KEYWORD

nonn

AUTHOR

Ray Chandler & Artur Jasinski, Dec 28 2008

EXTENSIONS

Terms a(8) and onward from Robert G. Wilson v, Sep 01 2014

STATUS

approved

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Last modified April 24 16:06 EDT 2019. Contains 322430 sequences. (Running on oeis4.)