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%I #27 Oct 23 2022 03:49:12
%S 1,3,6,36,30,90,180,210,420,630,1890,1260,2520,6930,18480,20790,13860,
%T 27720,41580,83160,138600,245700,235620,180180,556920,360360,540540,
%U 1670760,1081080,1413720,2702700,2162160,6486480,3063060,8288280
%N Smallest number having exactly n triangular divisors.
%C 2*a(n) is smallest number having exactly n oblong divisors.
%C A007862(a(n)) = n and A007862(m) <> n for m < a(n).
%H Ray Chandler and Donovan Johnson, <a href="/A130317/b130317.txt">Table of n, a(n) for n = 1..100</a> (first 58 terms from Ray Chandler)
%F a(n) = A088726(n-1)/2 for n>1. - _Ray Chandler_, Jun 24 2008
%e a(3)=6: A007862(6)=#{1,2*(2+1)/2,3*(3+1)/2}=3;
%e a(4)=36: A007862(36)=#{1,2*(2+1)/2,3*(3+1)/2,8*(8+1)/2}=4;
%o (PARI) a(n) = my(k=1); while (sumdiv(k, d, ispolygonal(d,3)) != n, k++); k; \\ _Michel Marcus_, Jan 14 2022
%Y Cf. A007862, A088726, A130279.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, May 23 2007
%E Extended by _Ray Chandler_, Jun 24 2008
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