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 A079111 Numbers n such that 2*n+1 or n itself is prime. 0
 1, 2, 3, 5, 6, 7, 8, 9, 11, 13, 14, 15, 17, 18, 19, 20, 21, 23, 26, 29, 30, 31, 33, 35, 36, 37, 39, 41, 43, 44, 47, 48, 50, 51, 53, 54, 56, 59, 61, 63, 65, 67, 68, 69, 71, 73, 74, 75, 78, 79, 81, 83, 86, 89, 90, 95, 96, 97, 98, 99, 101, 103, 105, 107, 109, 111, 113, 114, 116 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Union of A000040 and A005097; complement of A077654. LINKS Table of n, a(n) for n=1..69. FORMULA a(n) ~ (n log n)/2. - Charles R Greathouse IV, Jun 13 2017 PROG (PARI) is(n)=isprime(n) || isprime(2*n+1) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Sequence in context: A341763 A201144 A095274 * A346725 A346726 A346724 Adjacent sequences: A079108 A079109 A079110 * A079112 A079113 A079114 KEYWORD nonn AUTHOR Reinhard Zumkeller, Dec 24 2002 STATUS approved

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Last modified September 29 00:22 EDT 2023. Contains 365739 sequences. (Running on oeis4.)