%I A049439
%S A049439 1,2,4,8,9,16,18,32,36,64,72,128,144,225,256,288,441,450,512,576,625,
%T A049439 882,900,1024,1089,1152,1250,1521,1764,1800,2025,2048,2178,2304,2500,
%U A049439 2601,3042,3249,3528,3600,4050,4096,4356,4608,4761,5000,5202,5625,6084
%N A049439 Numbers n such that the number of odd divisors of n is an odd divisor 
               of n.
%C A049439 Invented by the HR concept formation program.
%C A049439 a(n) = A000079(k)*A016754(m) for appropriate k, m. - Reinhard Zumkeller 
               (reinhard.zumkeller(AT)gmail.com), Jun 05 2008
%H A049439 R. Zumkeller, <a href="b049439.txt">Table of n, a(n) for n = 1..1000</
               a>
%H A049439 S. Colton, <a href="http://www.cs.uwaterloo.ca/journals/JIS/index.html">
               Refactorable Numbers - A Machine Invention</a>, J. Integer Sequences, 
               Vol. 2, 1999, #2.
%H A049439 S. Colton, <a href="http://www.dai.ed.ac.uk/homes/simonco/research/hr/
               ">HR - Automatic Theory Formation in Pure Mathematics</a>
%e A049439 There are 3 odd divisors of 18, namely 1,3 and 9 and 3 itself is an odd 
               divisor of 9.
%Y A049439 Contains A000079 and A033950, Cf. A036896.
%Y A049439 Sequence in context: A080025 A152111 A025611 this_sequence A079931 A055008 
               A046678
%Y A049439 Adjacent sequences: A049436 A049437 A049438 this_sequence A049440 A049441 
               A049442
%K A049439 nice,nonn
%O A049439 1,2
%A A049439 Simon Colton (simonco(AT)cs.york.ac.uk)