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A057942 Pseudoprimes k to base 2 such that k-2 and k+2 are primes. 9


%S 645,25761,212421,332949,656601,6212361,63560685,413435121,1112691009,

%T 1121315385,1239702465,2851612221,5616154545,6454103601,6689540901,

%U 9691152801,9728582781,11970358401,12028438605,15076352901,17402551365

%N Pseudoprimes k to base 2 such that k-2 and k+2 are primes.

%C B-file extended using Feitsma's tables of pseudoprimes. - _Giovanni Resta_, Aug 20 2018

%H Giovanni Resta, <a href="/A057942/b057942.txt">Table of n, a(n) for n = 1..7000</a> (first 73 terms from Amiram Eldar)

%H C. K. Caldwell, <a href="http://primes.utm.edu/glossary/page.php?sort=Pseudoprime">Pseudoprimes</a>

%H Jan Feitsma and William Galway, <a href="http://www.cecm.sfu.ca/Pseudoprimes/index-2-to-64.html">Tables of pseudoprimes and related data</a>

%H Andrzej Rotkiewicz, <a href="http://dml.cz/dmlcz/137472">On pseudoprimes having special forms and a solution of K. Szymiczek's problem</a>, Acta Mathematica Universitatis Ostraviensis, Vol. 13, No. 1 (2005), pp. 57-71.

%H <a href="/index/Ps#pseudoprimes">Index entries for sequences related to pseudoprimes</a>

%Y Cf. A001567.

%K nonn

%O 1,1

%A _Patrick De Geest_, Oct 15 2000

%E More terms from _Don Reble_, Nov 03 2001

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Last modified May 18 19:58 EDT 2021. Contains 344002 sequences. (Running on oeis4.)