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A262983 Terms of A005179 divisible by their indices in order of appearance in A005179.

%I A262983 #42 Dec 15 2021 23:35:22
%S A262983 1,2,12,24,36,60,180,240,360,720,1260,1680,3600,6720,5040,10080,32400,
%T A262983 15120,20160,25200,60480,55440,810000,100800,181440,110880,226800,
%U A262983 221760,277200,907200,665280,1587600,720720,5670000,1108800,3548160,1995840,1441440,2494800,6350400
%N A262983 Terms of A005179 divisible by their indices in order of appearance in A005179.
%C A262983 A005179(n) is in this sequence iff it is divisible by n. Thus this is a subsequence of A005179 indexed by A262981.
%C A262983 Also this sequence is the intersection of A033950 and A005179. Hence this sequence has density zero. - _Vladimir Letsko_, Dec 16 2016
%C A262983 It seems that this sequence is a subsequence of A262981.
%C A262983 This sequence is not in ascending order as terms of A005179 divisible by their number of divisors do not occur in ascending order. For terms sorted in ascending order see A110821. - _David A. Corneth_, Dec 10 2021
%H A262983 David A. Corneth, <a href="/A262983/b262983.txt">Table of n, a(n) for n = 1..10000</a>
%H A262983 Vladimir Letsko, <a href="/A262983/a262983_1.txt">The table of correspondence between A262983 and A262981</a>
%F A262983 a(n) = A005179(A262981(n)).
%F A262983 A000005(a(n)) = A262981(n).
%e A262983 12 is a term since it is the smallest positive integer having exactly 6 divisors and divisible by 6.
%t A262983 Take[#, 33] &@ DeleteCases[#, 0] &@ Function[s, ReplacePart[#, Flatten@ Map[{# -> Function[k, k Boole[Divisible[k, #]]]@ Lookup[s, #]} &, Keys@ s]] &@ ConstantArray[0, Max@ Keys@ s]]@ Map[First, KeySort@ PositionIndex@ Table[DivisorSigma[0, n], {n, 10^7}]] (* _Michael De Vlieger_, Dec 11 2016, Version 10 *)
%Y A262983 Cf. A000005, A033950, A005179, A110821, A262981, A279373.
%K A262983 nonn,look
%O A262983 1,2
%A A262983 _Vladimir Letsko_, Oct 06 2015
%E A262983 Name clarified by _David A. Corneth_, Dec 10 2021