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 A171666 Numbers n such that n, n+1 and n+2 have the same number of divisors, and that number of divisors is larger than 4. 3
 230, 242, 243, 374, 603, 663, 902, 1105, 1274, 1309, 1334, 1832, 1885, 1924, 2013, 2054, 2133, 2264, 2343, 2504, 2523, 2665, 2696, 2936, 3110, 3655, 3656, 3729, 4203, 4401, 4503, 4504, 4614, 4669, 4695, 4807, 4923, 5133, 5862, 5943, 5944, 6054, 6061 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 MATHEMATICA f[n_]:=Length[Divisors[n]]; lst={}; Do[If[f[n]==f[n+1]==f[n+2]&&f[n]>4, AppendTo[lst, n]], {n, 8!}]; lst Flatten[Position[Partition[DivisorSigma[0, Range[7000]], 3, 1], _?(Length[ Union[#]]==1&&#[[1]]>4&), {1}, Heads->False]] (* Harvey P. Dale, Jul 20 2014 *) SequencePosition[Table[If[DivisorSigma[0, n]>4, DivisorSigma[0, n], n], {n, 6100}], {x_, x_, x_}][[All, 1]] (* Harvey P. Dale, Nov 15 2021 *) CROSSREFS Cf. A005237, A005238, A171665 Sequence in context: A072020 A177826 A122269 * A321503 A140077 A215217 Adjacent sequences: A171663 A171664 A171665 * A171667 A171668 A171669 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Dec 14 2009 STATUS approved

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Last modified December 5 00:23 EST 2023. Contains 367565 sequences. (Running on oeis4.)