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 A230559 Pseudoprimes n to base 2 such that n-2, n+2 and n+4 are primes. 3
 634038307449, 4846359321105, 11927878640385, 20835183400305, 34166605315305, 54096163177785, 63154533545265, 88365393281985, 189080281720065, 850943773070385, 917252751841665, 1278728202166185, 1602254869802049, 3742704749436465, 6082185264252945 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All numbers in this sequence end in either 5 or 9. LINKS Shyam Sunder Gupta, Table of n, a(n) for n = 1..82 EXAMPLE 634038307449 is a pseudoprime (base 2) and 634038307447, 634038307451 and 634038307453 are primes. CROSSREFS Cf. A001567, A057942, A230488, A230489, A228575. Sequence in context: A306500 A306891 A297006 * A105302 A015421 A180612 Adjacent sequences:  A230556 A230557 A230558 * A230560 A230561 A230562 KEYWORD nonn AUTHOR Shyam Sunder Gupta, Oct 27 2013 STATUS approved

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Last modified December 14 01:19 EST 2019. Contains 329978 sequences. (Running on oeis4.)