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%I #18 May 22 2021 17:41:20
%S 2,3,14,15,21,22,26,27,33,34,35,38,39,44,45,57,58,75,76,85,86,87,93,
%T 94,95,98,99,104,105,116,117,118,119,122,123,133,134,135,136,141,142,
%U 143,145,146,147,148,158,159,171,172,177,178,189,190,201,202,203
%N Runs of consecutive numbers with the same number of divisors.
%C The first run of length 3 is {33,34,35}; the first of length 4: {116, 117, 118, 119}; of length 5: {2641, 2642, 2643, 2644, 2645}; of length 6: {1081, 1082, 1083, 1084, 1085, 1086}; of length 7: {25781, 25782, 25783, 25784, 25785, 25786, 25787}; of length 8: {77673, 77674, 77675, 77676, 77677, 77678, 77679, 77680}.
%H Vincenzo Librandi, <a href="/A225756/b225756.txt">Table of n, a(n) for n = 1..1000</a>
%e Sequence begins:
%e 2, 3;
%e 14, 15;
%e 21, 22;
%e 26, 27;
%e 33, 34, 35;
%e 38, 39;
%e etc.
%t sel = Select[Range[300], DivisorSigma[0, #] == DivisorSigma[0, # + 1] &]; Union[sel, sel + 1]
%t Flatten[SequencePosition[DivisorSigma[0,Range[300]],{x_,x_}]]//Union (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, May 22 2021 *)
%Y Cf. A225757 (same sum of divisors).
%Y Cf. A225758 (same number and sum of divisors).
%Y Cf. A140578 (first term of every run).
%K nonn,easy,tabf
%O 1,1
%A _Jean-François Alcover_, May 15 2013
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