%I #17 Jul 09 2020 04:34:03

%S 30923,74849,96675,145674,152339,204323,230346,240425,255186,274547,

%T 276650,338921,361322,430073,432474,527922,574674,671346,671347,

%U 675491,697073,801473,808155,826825,826826,915857,939321,978675,998522

%N Least of five consecutive numbers which are cubefree and not squarefree, i.e., {k, k+1, k+2, k+3, k+4} are in A067259.

%H Amiram Eldar, <a href="/A071124/b071124.txt">Table of n, a(n) for n = 1..10000</a>

%F A051903(k) = A051903(k+1) = A051903(k+2) = A051903(k+3) = A051903(k+4) = 2.

%e 30923 = 17*17*107;

%e 30924 = 2*2*3*3*859;

%e 30925 = 5*5*1237;

%e 30926 = 2*7*47*47;

%e 30927 = 3*13*13*61.

%t With[{s = Select[Range[10^6], And[MemberQ[#, 2], FreeQ[#, k_ /; k > 2]] &@ FactorInteger[#][[All, -1]] &]}, Function[t, Part[s, #] &@ SequencePosition[t, {1, 1, 1, 1}][[All, 1]]]@ Differences@ s] (* _Michael De Vlieger_, Jul 30 2017 *)

%Y Cf. A051903, A063528, A067259.

%K nonn

%O 1,1

%A _Labos Elemer_, May 29 2002