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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.

A187743 Smallest number which is an unordered sum of two odd abundant numbers in exactly n ways.

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%I A187743 #13 Jan 03 2013 16:02:19
%S A187743 1890,3150,4410,5670,6930,8190,9450,10710,11970,12600,14490,13860,
%T A187743 15750,17010,20160,19530,22050,20790,23940,24570,26460,28350,28980,
%U A187743 64680,27720,32130,32760,38430,39690,40320,34650,51660,53550,56700,41580,58590,48510,70560
%N A187743 Smallest number which is an unordered sum of two odd abundant numbers in exactly n ways.
%C A187743 The first 10000 terms are all divisible by 210.
%H A187743 Donovan Johnson, <a href="/A187743/b187743.txt">Table of n, a(n) for n = 1..10000</a>
%e A187743 Summands are odd abundant numbers.
%e A187743 a(1) = 1890 = 945 + 945.
%e A187743 a(2) = 3150 = 945 + 2205 = 1575 + 1575.
%e A187743 a(3) = 4410 = 945 + 3465 = 1575 + 2835 = 2205 + 2205.
%e A187743 a(4) = 5670 = 945 + 4725 = 1575 + 4095 = 2205 + 3465 = 2835 + 2835.
%o A187743 (PARI) /* finds first 1000 terms */ mx=4616430; ct=vector(mx); k=9384; v=vector(k); n=vector(1000); c=0; forstep(i=945, mx-1, 2, if(sigma(i)-2*i>0, c++; v[c]=i)); for(i=1, k, for(j=i, k, s=v[i]+v[j]; if(s<=mx, ct[s]++, next(2)))); forstep(i=1890, mx, 2, if(ct[i]>0 && ct[i]<=1000 && n[ct[i]]==0, n[ct[i]]=i)); for(i=1, 1000, write("b187743.txt", i " " n[i]))
%Y A187743 Cf. A005231, A168226.
%K A187743 nonn
%O A187743 1,1
%A A187743 _Donovan Johnson_, Jan 03 2013