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 A066529 a(n) is the least index such that the least primitive root of the a(n)-th prime is n, or zero if no such prime exists. 5
 1, 2, 4, 0, 9, 13, 20, 0, 0, 65, 117, 566, 88, 173, 85, 0, 64, 5426, 43, 10217, 80, 474, 326, 44110, 0, 1479, 0, 12443, 1842, 11662, 775, 0, 23559, 5029, 6461, 0, 3894, 5629, 15177, 105242, 14401, 182683, 9204, 7103, 5518399, 23888, 24092, 42304997, 0, 1455704, 27848, 12107, 14837, 205691645, 38451, 12102037, 39370, 28902, 57481, 56379, 90901, 53468, 5918705, 0, 732055, 1738826, 242495, 265666, 10523, 388487, 260680 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The corresponding primes are in A023048. For n < 150, only a(108) is presently unknown. - Robert G. Wilson v, Jan 03 2006 LINKS Tomás Oliveira e Silva, Least prime primitive root of prime numbers E. Weisstein, Primitive Roots FORMULA a(n) = 0 iff n is a perfect power (A001597) > 1. - Robert G. Wilson v, Jan 03 2006 a(n) = min { k | A001918(k) = n } U {0} = A000720(A023048(n)) (or zero). - M. F. Hasler, Jun 01 2018 EXAMPLE a(6) = 13 because Prime[13] = 41 is the least prime with least primitive root = 6 MATHEMATICA big = Table[ p = Prime[ n ]; PrimitiveRoot[ p ], {n, 1, 1000000} ]; Flatten[ Table[ Position[ big, n, 1, 1 ]/.{}-> 0, {n, 79} ] ] (* First load package NumberTheory`NumberTheoryFunctions` *) (* first load package *) << NumberTheory`NumberTheoryFunctions` (* then do *) t = Table[0, {100}]; Do[a = PrimitiveRoot@Prime@n; If[a < 101 && t[[a]] == 0, t[[a]] = n], {n, 10^6}]; t (* Robert G. Wilson v, Dec 15 2005 *) CROSSREFS Cf. A001918, A001122, A001123, A023048, A001597. Sequence in context: A095059 A021419 A180192 * A052080 A261754 A073451 Adjacent sequences:  A066526 A066527 A066528 * A066530 A066531 A066532 KEYWORD nonn AUTHOR Wouter Meeussen, Jan 06 2002 EXTENSIONS Edited by Dean Hickerson, Jan 14 2002 Further terms from Robert G. Wilson v, Jan 03 2006 STATUS approved

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Last modified June 5 18:48 EDT 2020. Contains 334854 sequences. (Running on oeis4.)