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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.

A292832 a(n) is the least positive k, not a power of 2, such that the Hamming weight of k equals the Hamming weight of k^n, or 0 if no such k exists.

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%I A292832 #18 Feb 01 2024 00:08:04
%S A292832 3,3,56953,34225258495
%N A292832 a(n) is the least positive k, not a power of 2, such that the Hamming weight of k equals the Hamming weight of k^n, or 0 if no such k exists.
%C A292832 The Hamming weight of a number n is given by A000120(n).
%C A292832 Is this sequence positive for every positive integer?
%C A292832 a(2) = A292787(2).
%C A292832 a(3) = A292788(2).
%e A292832 For n = 2:
%e A292832 - 1 is a power of 2,
%e A292832 - 2 is a power of 2,
%e A292832 - A000120(3) = 2 and A000120(3^2) = 2,
%e A292832 - hence a(2) = 3.
%o A292832 (PARI) a(n) = forstep(k=3, oo, 2, if (hammingweight(k) == hammingweight(k^n), return (k)))
%Y A292832 Cf. A000120, A292787, A292788, A363836.
%K A292832 nonn,base,hard,more
%O A292832 1,1
%A A292832 _Rémy Sigrist_, Sep 24 2017