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%I #8 Jul 30 2016 16:19:37
%S 3,3,3,3,5,7,3,3,3,3,11,5,3,3,3,3,5,19,3,3,3,3,23,5,3,3,3,3,29,31,3,3,
%T 3,3,5,37,3,3,3,3,41,5,3,3,3,3,5,7,3,3,3,3,53,5,3,3,3,3,7,11,3,3,3,3,
%U 5,7,3,3,3,3,11,5,3,3,3,3,5,79,3,3,3,3,83,5,3,3,3,3,89,7,3,3,3,3,5,97,3,3,3
%N Smallest prime factor of n-th odd triangular number.
%C As A014493(n)=binomial(A042963(n),2) and a(n)=A020639(A014493(n))>2, A014493(n) is a good binomial coefficient.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TriangularNumber.html">Triangular Number</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GoodBinomialCoefficient.html">Good Binomial Coefficient</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LeastPrimeFactor.html">Least Prime Factor</a>.
%t FactorInteger[#][[1,1]]&/@Rest[Select[Accumulate[Range[200]],OddQ]] (* _Harvey P. Dale_, Jul 30 2016 *)
%Y Cf. A069901.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Mar 11 2003
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