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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A075039 Smallest of three consecutive squarefree numbers having equal numbers of prime factors.

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%I A075039 #15 Feb 24 2021 03:52:58
%S A075039 33,85,93,141,201,213,217,301,393,445,633,697,921,1041,1137,1261,1309,
%T A075039 1345,1401,1641,1761,1837,1885,1893,1941,1981,2013,2101,2181,2217,
%U A075039 2305,2361,2433,2461,2517,2641,2665,2721,2733,3097,3385,3601,3693,3729,3865
%N A075039 Smallest of three consecutive squarefree numbers having equal numbers of prime factors.
%H A075039 Amiram Eldar, <a href="/A075039/b075039.txt">Table of n, a(n) for n = 1..10000</a>
%F A075039 A001221(a(n)) = A001222(a(n)) = A001221(a(n)+1) = A001222(a(n)+1).
%e A075039 33 is a member as 33, 34 and 35 are of the form p*q where p and q are primes.
%t A075039 Select[Range[4000], AllTrue[# + Range[0, 2], SquareFreeQ] && Equal @@ PrimeNu[# + Range[0, 2]] &] (* _Amiram Eldar_, Feb 24 2021 *)
%Y A075039 Cf. A001221, A001222, A005117, A052214, A086263, A039833.
%K A075039 nonn
%O A075039 1,1
%A A075039 _Amarnath Murthy_, Sep 03 2002
%E A075039 More terms from _Matthew Conroy_, Sep 08 2002
%E A075039 Edited by _Reinhard Zumkeller_, Jul 14 2003
%E A075039 Offset corrected by _Amiram Eldar_, Feb 24 2021