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A230487 Strong pseudoprimes n to base 2 such that either n-2 or n+2 is prime. 1
4681, 29341, 42799, 49141, 52633, 85489, 90751, 104653, 253241, 280601, 458989, 580337, 1004653, 1082401, 1207361, 1251949, 1302451, 1678541, 1907851, 1909001, 2419385, 2510569, 2811271, 3090091, 3539101, 5044033, 5049001, 5173601, 5489641, 5590621, 7177105 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Shyam Sunder Gupta, Table of n, a(n) for n = 1..5001

EXAMPLE

4681 is a strong pseudoprime (base 2) and 4679 is prime. 253241 is a strong pseudoprime (base 2) and 253243 is prime.

CROSSREFS

Cf. A001567, A001262, A230483, A230484, A230485.

Sequence in context: A236014 A202431 A066731 * A230483 A022244 A252382

Adjacent sequences:  A230484 A230485 A230486 * A230488 A230489 A230490

KEYWORD

nonn

AUTHOR

Shyam Sunder Gupta, Oct 20 2013

STATUS

approved

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Last modified April 19 01:29 EDT 2019. Contains 322237 sequences. (Running on oeis4.)