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A153581 Pseudoprimes to bases 2,3,5 and 7 which are not Carmichael numbers (A002997). 4

%I #24 Jun 25 2019 05:41:19

%S 721801,8646121,10403641,22885129,36307981,42702661,46094401,48064021,

%T 52204237,79398901,80918281,81954133,114329881,116151661,143168581,

%U 170782921,188985961,217145881,220531501,282707461,299671921,303373801,326695141,353815801,361307521

%N Pseudoprimes to bases 2,3,5 and 7 which are not Carmichael numbers (A002997).

%C Terms congruent to 5 (mod 6): 468950021, 493108481, 659846021, 5936122901, 8144063621, ... - _Robert G. Wilson v_, Sep 03 2014

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

%H Amiram Eldar, <a href="/A153581/b153581.txt">Table of n, a(n) for n = 1..1077</a> (terms 1..125 from Robert G. Wilson v)

%t 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_, Dec 28 2008; corrected by _Robert G. Wilson v_, Sep 01 2014 *)

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

%K nonn

%O 1,1

%A _Ray Chandler_ & _Artur Jasinski_, Dec 28 2008

%E Terms a(8) and onward from _Robert G. Wilson v_, Sep 01 2014

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Last modified April 25 01:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)