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A230489 Pseudoprimes n to base 2 such that n+2 and n+4 are primes. 4
87249, 831405, 1489665, 2113665, 31880577, 81612105, 84028407, 86559045, 274014885, 1778357505, 1853263365, 2276082537, 9090685605, 12300409857, 43620860865, 69654751377, 248342283645, 634038307449, 848282877345, 1123296404385, 1344952805505, 3307428792777 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Shyam Sunder Gupta, Table of n, a(n) for n = 1..1076

EXAMPLE

87249 is a pseudoprime (base 2) and 87251 and 87253 are primes.

CROSSREFS

Cf. A001567, A057942.

Sequence in context: A216257 A237410 A206632 * A098186 A069313 A022207

Adjacent sequences:  A230486 A230487 A230488 * A230490 A230491 A230492

KEYWORD

nonn

AUTHOR

Shyam Sunder Gupta, Oct 20 2013

STATUS

approved

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Last modified June 22 21:29 EDT 2021. Contains 345393 sequences. (Running on oeis4.)