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.

A175065 Smallest number m for which there are exactly n ways to write m as x^y with x >= 2, y >= 1.

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%I A175065 #32 Feb 02 2025 19:57:57
%S A175065 2,4,16,64,65536,4096,18446744073709551616,16777216,68719476736,
%T A175065 281474976710656
%N A175065 Smallest number m for which there are exactly n ways to write m as x^y with x >= 2, y >= 1.
%C A175065 a(11) is 2^1024 and is too big to display. - _Joerg Arndt_, Aug 17 2016.
%C A175065 a(n) is the smallest order of a finite field with exactly n subfields. - _Jianing Song_, Feb 02 2025
%H A175065 Alois P. Heinz, <a href="/A175065/b175065.txt">Table of n, a(n) for n = 1..12</a>
%F A175065 a(n) = 2^d(s) where s is the least number having d(s) = A000005(s) = n. - _David A. Corneth_, Aug 17 2016
%F A175065 a(n) = 2^A005179(n). - _Joerg Arndt_, Aug 17 2016
%e A175065 For n = 6, a(6) = 4096: there are 6 ways to write 4096 as x^y: 4096^1 = 64^2 = 16^3 = 8^4 = 4^6 = 2^12.
%e A175065 a(7) = 2^64, a(8) = 16777216. See A175064, A001597.
%Y A175065 Cf. A000005, A001597, A175064.
%K A175065 nonn
%O A175065 1,1
%A A175065 _Jaroslav Krizek_, Jan 23 2010
%E A175065 More terms from _David A. Corneth_ and _Joerg Arndt_, Aug 17 2016
%E A175065 Edited by _N. J. A. Sloane_, Aug 18 2016
%E A175065 a(1) prepended by _Jianing Song_, Feb 02 2025