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 A049051 Numbers n such that n through n+4 all have same number of divisors. 10
 11605, 12855, 13782, 19142, 21494, 28374, 28375, 40311, 42805, 50582, 55254, 60231, 60663, 79094, 87655, 90181, 90182, 95845, 99655, 103621, 109765, 115591, 120727, 121045, 122151, 122871, 142454, 142806, 152630, 157493, 157494, 171893 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Donovan Johnson, Table of n, a(n) for n = 1..1000 MAPLE with(numtheory); A049051:=proc(q, w) local k, ok, n; for n from 1 to q do ok:=1; for k from 1 to w do if tau(n)<>tau(n+k) then ok:=0; break; fi; od; if ok=1 then print(n); fi; od; end: A049051(10^6, 4); # Paolo P. Lava, May 03 2013 MATHEMATICA Flatten[Position[Partition[DivisorSigma[0, Range[200000]], 5, 1], _?(Length[ Union[#]] == 1&), {1}, Heads->False]] (* Harvey P. Dale, May 30 2014 *) SequencePosition[DivisorSigma[0, Range[200000]], {x_, x_, x_, x_, x_}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 03 2017 *) CROSSREFS Cf. A000005, A005237, A005238, A006601, A006558, A019273, A039665, A049052, A049053. Sequence in context: A226905 A162865 A237534 * A250242 A231321 A154053 Adjacent sequences:  A049048 A049049 A049050 * A049052 A049053 A049054 KEYWORD nonn AUTHOR STATUS approved

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Last modified February 19 18:22 EST 2019. Contains 320327 sequences. (Running on oeis4.)