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%I #36 Oct 30 2022 15:08:59
%S 120,210,1540,7140,11628,24310,61218182743304701891431482520
%N Numbers that appear as binomial coefficients exactly 6 times.
%H Jean-Marie de Koninck, Nicolas Doyon, and William Verreault, <a href="https://arxiv.org/abs/2107.09107">Repetitions of multinomial coefficients and a generalization of Singmaster's conjecture</a>, arXiv:2107.09107 [math.NT], 2021.
%H Zoe Griffiths, <a href="https://www.youtube.com/watch?v=Z3xq4ODNeZs">My MegaFavNumber: 61,218,182,743,304,701,891,431,482,520</a>, YouTube video, 2020.
%H David Singmaster, <a href="https://doi.org/10.1080/00029890.1971.11992769">How Often Does An Integer Occur As A Binomial Coefficient?</a>, American Mathematical Monthly, 78(4), 1971, pp. 385-386; also on <a href="https://fermatslibrary.com/s/how-often-does-an-integer-occur-as-a-binomial-coefficient">Fermat's Library</a>.
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Singmaster's_conjecture">Singmaster's conjecture</a>
%H <a href="/index/Pas#Pascal">Index entries for triangles and arrays related to Pascal's triangle</a>
%F A059233(a(n)) = 3. - _Reinhard Zumkeller_, Dec 24 2012
%o (Haskell)
%o import Data.List (elemIndices)
%o a098565 n = a098565_list !! (n-1)
%o a098565_list = map (+ 2 ) $ elemIndices 3 a059233_list
%o -- _Reinhard Zumkeller_, Dec 24 2012
%Y See A098564 for more information.
%Y Cf. A185024, A182237. Subsequence of A003015.
%Y Cf. A059233.
%K nonn,more
%O 1,1
%A _Paul D. Hanna_, Oct 27 2004
%E a(7) from _T. D. Noe_, Jul 13 2005
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