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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.

A060683 Numbers for which the differences between consecutive divisors (ordered by size) are distinct.

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%I A060683 #25 Nov 11 2023 10:39:30
%S A060683 1,2,3,4,5,7,8,9,10,11,13,14,16,17,19,21,22,23,25,26,27,28,29,31,32,
%T A060683 33,34,35,37,38,39,41,43,44,46,47,49,50,51,52,53,55,57,58,59,61,62,64,
%U A060683 65,67,68,69,71,73,74,76,77,79,81,82,83,85,86,87,88,89,92,93,94,95,97,98
%N A060683 Numbers for which the differences between consecutive divisors (ordered by size) are distinct.
%C A060683 A060682(a(n)) = A000005(a(n)) - 1, n > 1. - _Reinhard Zumkeller_, Jun 25 2015
%H A060683 Reinhard Zumkeller, <a href="/A060683/b060683.txt">Table of n, a(n) for n = 1..10000</a>
%H A060683 A. Balog, P. Erdős, and G. Tenenbaum, <a href="http://dx.doi.org/10.1007/978-1-4612-3464-7_6">On Arithmetic Functions Involving Consecutive Divisors</a>, In: Analytical Number Theory, pp. 77-90, Birkhäuser, Basel, 1990.
%e A060683 For n=6, divisors={1,2,3,6}; differences={1,1,3}, which are not distinct, so 6 is not in the sequence.
%t A060683 test[n_ ] := Length[dd=Drop[d=Divisors[n], 1]-Drop[d, -1]]==Length[Union[dd]]; Select[Range[1, 100], test]
%o A060683 (Haskell)
%o A060683 a060683 n = a060683_list !! (n-1)
%o A060683 a060683_list = 1 : filter (\x -> a060682 x == a000005' x - 1) [2..]
%o A060683 -- _Reinhard Zumkeller_, Jun 25 2015
%o A060683 (PARI) isok(k) = my(d=divisors(k)); #Set(vector(#d-1, k, d[k+1]-d[k])) == #d-1; \\ _Michel Marcus_, Nov 11 2023
%Y A060683 Cf. A000005, A060680, A060681, A060682, A060765.
%Y A060683 Cf. A060682, A259366 (complement).
%K A060683 nonn
%O A060683 1,2
%A A060683 _Labos Elemer_, Apr 19 2001
%E A060683 Edited by _Dean Hickerson_, Jan 22 2002