%I A061017
%S A061017 1,2,2,3,3,4,4,4,5,5,6,6,6,6,7,7,8,8,8,8,9,9,9,10,10,10,10,11,11,12,12,
%T A061017 12,12,12,12,13,13,14,14,14,14,15,15,15,15,16,16,16,16,16,17,17,18,18,
%U A061017 18,18,18,18,19,19,20,20,20,20,20,20,21,21,21,21,22,22,22,22,23,23,24
%N A061017 List in which n appears d(n) times, where d(n) [A000005] is the number 
               of divisors of n.
%C A061017 The union of N, 2N, 3N, ..., where N = {1,2,3,4,5,6,...}. In other words, 
               the numbers {m*n, m>=1, n>=1} sorted into nondecreasing order.
%C A061017 Considering the maximal rectangle in each of the Ferrers graphs of partitions 
               of n, a(n) is the smallest such maximal rectangle; a(n) is also an 
               inverse of A006218. - Henry Bottomley (se16(AT)btinternet.com), Mar 
               11 2002
%C A061017 The numbers in A003991 arranged in numerical order. - Matthew Vandermast 
               (ghodges14(AT)comcast.net), Feb 28 2003
%H A061017 N. J. A. Sloane, <a href="b061017.txt">Table of n, a(n) for n = 1..7069</
               a>
%F A061017 a(n) >= pi(n+1) for all n; a(n) >= pi(n) + 1 for all n >= 24 (cf. A098357, 
               A088526, A006218, A052511). - N. J. A. Sloane (njas(AT)research.att.com), 
               Oct 22 2008
%p A061017 with(numtheory); t1:=[]; for i from 1 to 1000 do for j from 1 to tau(i) 
               do t1:=[op(t1),i]; od: od: t1:=sort(t1);
%t A061017 Flatten[Table[Table[n, {Length[Divisors[n]]}], {n, 1, 30}]]
%o A061017 (PARI) a(n)=if(n<0,0,t=1;while(sum(k=1,t,floor(t/k))<n,t++);t) [From 
               Benoit Cloitre (benoit7848c(AT)orange.fr), Nov 08 2009]
%Y A061017 Cf. A000005. An inverse to A006218.
%Y A061017 Sequence in context: A024417 A060021 A000006 this_sequence A088462 A093337 
               A120397
%Y A061017 Adjacent sequences: A061014 A061015 A061016 this_sequence A061018 A061019 
               A061020
%K A061017 nonn,easy,new
%O A061017 1,2
%A A061017 Jont Allen (jba(AT)research.att.com), May 25 2001
%E A061017 More terms from Erich Friedman (efriedma(AT)stetson.edu), Jun 01 2001