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.

A344312 Number k such that k and k+1 have the same number of exponential divisors (A049419).

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%I A344312 #8 May 16 2021 02:41:35
%S A344312 1,2,5,6,8,10,13,14,21,22,24,27,29,30,33,34,37,38,41,42,44,46,49,57,
%T A344312 58,61,65,66,69,70,73,75,77,78,80,82,85,86,93,94,98,101,102,105,106,
%U A344312 109,110,113,114,116,118,120,122,124,125,129,130,133,135,137,138,141
%N A344312 Number k such that k and k+1 have the same number of exponential divisors (A049419).
%H A344312 Amiram Eldar, <a href="/A344312/b344312.txt">Table of n, a(n) for n = 1..10000</a>
%e A344312 1 is a term since A049419(1) = A049419(2) = 1.
%e A344312 8 is a term since A049419(8) = A049419(9) = 2.
%t A344312 f[p_, e_] := DivisorSigma[0, e]; ed[n_] := Times @@ f @@@ FactorInteger[n]; Select[Range[200], ed[#] == ed[# + 1] &]
%Y A344312 Cf. A049419.
%Y A344312 Similar sequences: A005237, A006049, A343819, A344313, A344314.
%K A344312 nonn
%O A344312 1,2
%A A344312 _Amiram Eldar_, May 14 2021