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A230483
Strong pseudoprimes (base 2) that become prime when two is subtracted.
4
4681, 29341, 42799, 49141, 52633, 85489, 90751, 104653, 458989, 1004653, 1082401, 1251949, 1302451, 1907851, 2510569, 2811271, 3090091, 3539101, 5044033, 5049001, 5489641, 5590621, 7177105, 9069229, 9073513, 9567673, 9995671, 10323769, 11473885, 12263131
OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..5001 from Shyam Sunder Gupta)
EXAMPLE
4681 is a strong pseudoprime (base 2) and 4679 is prime.
CROSSREFS
KEYWORD
nonn
AUTHOR
Shyam Sunder Gupta, Oct 20 2013
STATUS
approved