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 A067185 Numbers k such that prime(k+1) + prime(k) == 1 (mod k). 3
 1, 7, 17, 109, 281, 1669, 6592663, 16899113, 16899145, 16899295, 749973611, 5067034877, 5067034925, 34487825911, 1626582230375 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS MATHEMATICA a = b = 0; Do[b = Prime[n + 1]; If[Mod[a + b, n] == 1, Print[n]]; a = b, {n, 1, 10^9}] PROG (Sage) def A067185(max):     terms = []     p = 2     for n in range(1, max + 1):         q = next_prime(p)         if not (p + q - 1) % n:             terms.append(n)         p = q     return terms # Eric M. Schmidt, Feb 05 2013 (PARI) isok(k) = (prime(k+1) + prime(k)) % k == 1; \\ Michel Marcus, Feb 17 2021 CROSSREFS Cf. A066895 (== 0 instead of 1). Sequence in context: A181605 A284209 A068172 * A205989 A262474 A284416 Adjacent sequences:  A067182 A067183 A067184 * A067186 A067187 A067188 KEYWORD nonn,more AUTHOR Benoit Cloitre, Feb 19 2002 EXTENSIONS Edited and extended by Robert G. Wilson v, Feb 19 2002 Extended by David W. Wilson, Feb 20 2002 a(11)-a(14) from Donovan Johnson, Mar 10 2010 First term from Eric M. Schmidt, Feb 05 2013 STATUS approved

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Last modified April 21 07:26 EDT 2021. Contains 343146 sequences. (Running on oeis4.)