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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.

A049053 Numbers k such that k through k+6 all have the same number of divisors.

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%I A049053 #40 Apr 11 2024 04:05:02
%S A049053 171893,180965,647381,1039493,1071829,1450261,1563653,1713413,2129029,
%T A049053 2384101,4704581,4773301,5440853,5775365,6627061,6644405,6697253,
%U A049053 8556661,8833429,10531253,12101509,12238453,12307141,13416661,13970405
%N A049053 Numbers k such that k through k+6 all have the same number of divisors.
%C A049053 Allan Swett found that the first term not congruent to 5 mod 16 is 67073285. - _Ralf Stephan_, Nov 15 2004
%C A049053 Since A119479(n) < 7 for n < 8, no term has fewer than 8 divisors; the first that has more is a(30)=17476613. - _Ivan Neretin_, Feb 05 2016
%H A049053 Amiram Eldar, <a href="/A049053/b049053.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Donovan Johnson)
%H A049053 Jean-Marie De Koninck, Those Fascinating Numbers, Amer. Math. Soc., 2009, page 244.
%o A049053 (PARI) isok(n) = {my(nb = numdiv(n)); for (k=1, 6, if (numdiv(n+k) != nb, return (0));); 1;} \\ _Michel Marcus_, Feb 06 2016
%Y A049053 Cf. A000005, A006558, A019273, A119479.
%Y A049053 Other runs of equidivisor numbers: A005237 (runs of 2), A005238 (runs of 3), A006601 (runs of 4), A049051 (runs of 5), A049052 (runs of 6).
%K A049053 nonn
%O A049053 1,1
%A A049053 _David W. Wilson_