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.

A342187 Numbers k such that both k and k+1 are not exponentially odd numbers.

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%I A342187 #9 Mar 06 2021 06:00:15
%S A342187 44,48,49,63,75,80,98,99,116,147,171,175,207,244,260,275,288,315,324,
%T A342187 332,360,363,368,387,404,475,476,495,507,524,528,531,539,548,549,575,
%U A342187 603,604,624,636,656,675,692,724,725,747,764,774,800,819,832,844,845,846
%N A342187 Numbers k such that both k and k+1 are not exponentially odd numbers.
%C A342187 The numbers of terms not exceeding 10^k for k = 2, 3, ..., are 8, 64, 624, 6281, 62779, 627904, 6279725, 62796307, 627961560, ... Apparently this sequence has an asymptotic density 0.062796...
%H A342187 Amiram Eldar, <a href="/A342187/b342187.txt">Table of n, a(n) for n = 1..10000</a>
%e A342187 44 is a term since 44 = 2^2 * 11 and 45 = 3^2 * 5 both have an even exponent in their prime factorization.
%t A342187 expOddQ[n_] := AllTrue[FactorInteger[n][[;;, 2]], OddQ]; Select[Range[10^3], !expOddQ[#] && !expOddQ[# + 1] &]
%Y A342187 Cf. A072587, A268335.
%Y A342187 Similar sequences: A068140, A068781, A342188, A342189.
%K A342187 nonn
%O A342187 1,1
%A A342187 _Amiram Eldar_, Mar 04 2021