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A230488 Pseudoprimes n to base 2 such that n-2 and n-4 are primes. 4
645, 33153, 129921, 157641, 451905, 656601, 1608465, 3020361, 3370641, 6212361, 19092921, 34487601, 38790753, 681942801, 940492785, 1109260545, 1574300001, 2693081973, 3037396461, 4160578521, 6424683105, 7384487181, 13671360561, 14966031345, 15731001105 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Shyam Sunder Gupta, Table of n, a(n) for n = 1..7173

EXAMPLE

645 is a pseudoprime (base 2) and 643 and 641 are primes.

CROSSREFS

Cf. A001567, A057942.

Sequence in context: A265684 A067845 A057942 * A228575 A250989 A187434

Adjacent sequences:  A230485 A230486 A230487 * A230489 A230490 A230491

KEYWORD

nonn

AUTHOR

Shyam Sunder Gupta, Oct 20 2013

STATUS

approved

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Last modified May 7 08:12 EDT 2021. Contains 343636 sequences. (Running on oeis4.)