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%I #9 Jun 07 2020 01:19:53
%S 2068373,2948373,3571749,3916374,4730373,4757750,6755750,8109125,
%T 11290872,12248872,13071750,13648311,13903623,15278247,15448374,
%U 15449749,16793622,17446374,17991125,19407624,20080248,20250375,21594248,22577750,24190758,25297622,26140373
%N Starts of runs of 4 consecutive numbers that have an equal number of unitary and nonunitary divisors (A048109).
%H Amiram Eldar, <a href="/A335398/b335398.txt">Table of n, a(n) for n = 1..10000</a>
%e 2068373 is a term since 2068373, 2068374, 2068375 and 2068376 each have an equal number of unitary and nonunitary divisors. 2068373 and 2068375 each have 4 unitary divisors and 4 nonunitary divisors, 2068374 has 32 unitary divisors and 32 nonunitary divisors, and 2068376 has 8 unitary divisors and 8 nonunitary divisors.
%t q[n_] := DivisorSigma[0, n] == 2^(PrimeNu[n] + 1); v = q /@ Range[4]; seq = {}; Do[v = Append[Drop[v, 1], q[k]]; If[And @@ v, AppendTo[seq, k - 3]], {k, 5, 10^7}]; seq
%Y Subsequence of A048109, A335328 and A335397.
%Y Cf. A000005, A034444, A048105.
%K nonn
%O 1,1
%A _Zak Seidov_ and _Amiram Eldar_, Jun 06 2020
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