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 A078931 Numbers n such that n divides p(n)+1 or p(n)-1 where p(n) is the n-th prime. 1
 1, 2, 3, 4, 5, 6, 10, 12, 14, 70, 72, 181, 182, 440, 1053, 6458, 6459, 6460, 6461, 6466, 6471, 40087, 40089, 100362, 251712, 251732, 251737, 251742, 637236, 637320, 637334, 637336, 1617173, 4124466, 10553445, 10553455, 10553504, 10553505, 10553547, 10553569 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA Equals A023143 union A045924. EXAMPLE 181 is in the sequence because the 181st prime is 1087, and 1086 is divisible by 181 (although 1088 is not so divisible). MATHEMATICA ndpQ[n_]:=Module[{p=Prime[n]}, Divisible[p-1, n]||Divisible[p+1, n]]; Select[Range[100000], ndpQ]  (* Harvey P. Dale, Apr 03 2011 *) CROSSREFS Sequence in context: A018642 A116998 A285614 * A018779 A018382 A018266 Adjacent sequences:  A078928 A078929 A078930 * A078932 A078933 A078934 KEYWORD nonn AUTHOR Benoit Cloitre, Jan 12 2003 EXTENSIONS Corrected and example added by Harvey P. Dale, Apr 03 2011 Extended with terms from A023143 and A045924 by Michel Marcus, Nov 30 2013 STATUS approved

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Last modified September 21 07:08 EDT 2019. Contains 327253 sequences. (Running on oeis4.)