cp's OEIS Frontend

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.

A019273 First run of n consecutive integers with same number of divisors ends at a(n).

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%I A019273 #30 Feb 16 2024 01:20:30
%S A019273 1,3,35,245,11609,28379,171899,1043710445728,2197379769828,
%T A019273 2642166652554084
%N A019273 First run of n consecutive integers with same number of divisors ends at a(n).
%C A019273 The entry 40315 given in Guy and Wells is incorrect.
%C A019273 Terminating number in the sequence of consecutive integers with the same number of divisors in A006558. - _Jud McCranie_, Jan 14 2006
%D A019273 R. K. Guy "Unsolved Problems in Number Theory", section B18.
%D A019273 David Wells "Dictionary of Curious and Interesting Numbers" #40311.
%e A019273 phi(33)=phi(34)=phi(35), so a(3)=35
%Y A019273 Cf. A000005, A005237, A005238, A006601, A049051, A006558, A039665.
%Y A019273 a(n)=A006558(n)+n-1.
%K A019273 nonn,hard
%O A019273 1,2
%A A019273 _Jud McCranie_
%E A019273 More terms from _Jud McCranie_, Oct 04 2002
%E A019273 One more term from _Jud McCranie_, Jan 14 2006
%E A019273 a(10) by _Jud McCranie_, Nov 27 2018