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A057942 Pseudoprimes k to base 2 such that k-2 and k+2 are primes. 9
645, 25761, 212421, 332949, 656601, 6212361, 63560685, 413435121, 1112691009, 1121315385, 1239702465, 2851612221, 5616154545, 6454103601, 6689540901, 9691152801, 9728582781, 11970358401, 12028438605, 15076352901, 17402551365 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

B-file extended using Feitsma's tables of pseudoprimes. - Giovanni Resta, Aug 20 2018

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..7000 (first 73 terms from Amiram Eldar)

C. K. Caldwell, Pseudoprimes

Jan Feitsma and William Galway, Tables of pseudoprimes and related data

Andrzej Rotkiewicz,  On pseudoprimes having special forms and a solution of K. Szymiczek's problem, Acta Mathematica Universitatis Ostraviensis, Vol. 13, No. 1 (2005), pp. 57-71.

Index entries for sequences related to pseudoprimes

CROSSREFS

Cf. A001567.

Sequence in context: A063844 A265684 A067845 * A230488 A228575 A250989

Adjacent sequences:  A057939 A057940 A057941 * A057943 A057944 A057945

KEYWORD

nonn

AUTHOR

Patrick De Geest, Oct 15 2000

EXTENSIONS

More terms from Don Reble, Nov 03 2001

STATUS

approved

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Last modified September 17 19:12 EDT 2019. Contains 327137 sequences. (Running on oeis4.)