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 A138306 Least prime p such that 2n = p + g, where g is a prime primitive root of p, or 0 if there is no such prime p. 2
 0, 0, 0, 5, 7, 7, 0, 0, 11, 13, 17, 13, 0, 17, 23, 19, 23, 0, 0, 23, 23, 31, 43, 29, 37, 41, 37, 37, 41, 41, 43, 0, 47, 61, 41, 43, 67, 47, 47, 67, 59, 53, 73, 47, 47, 61, 53, 59, 67, 0, 59, 61, 59, 67, 97, 89, 97, 79, 71, 61, 79, 71, 73, 67, 71, 71, 97, 83, 71, 137, 113, 0, 103, 89 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Goldbach meets prime primitive prime roots. Sequence A138118 gives the number of representations for each 2n and sequence A138307 lists the values of 2n that are not represented. LINKS T. D. Noe, Table of n, a(n) for n=1..1000 CROSSREFS Cf. A138305 (prime primitive roots). Sequence in context: A314371 A217678 A227452 * A197257 A217175 A338558 Adjacent sequences: A138303 A138304 A138305 * A138307 A138308 A138309 KEYWORD nonn AUTHOR T. D. Noe, Mar 14 2008 STATUS approved

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Last modified September 11 06:30 EDT 2024. Contains 375814 sequences. (Running on oeis4.)