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A098565
Numbers that appear as binomial coefficients exactly 6 times.
8
120, 210, 1540, 7140, 11628, 24310, 61218182743304701891431482520
OFFSET
1,1
LINKS
Jean-Marie de Koninck, Nicolas Doyon, and William Verreault, Repetitions of multinomial coefficients and a generalization of Singmaster's conjecture, arXiv:2107.09107 [math.NT], 2021.
David Singmaster, How Often Does An Integer Occur As A Binomial Coefficient?, American Mathematical Monthly, 78(4), 1971, pp. 385-386; also on Fermat's Library.
FORMULA
A059233(a(n)) = 3. - Reinhard Zumkeller, Dec 24 2012
PROG
(Haskell)
import Data.List (elemIndices)
a098565 n = a098565_list !! (n-1)
a098565_list = map (+ 2 ) $ elemIndices 3 a059233_list
-- Reinhard Zumkeller, Dec 24 2012
CROSSREFS
See A098564 for more information.
Cf. A185024, A182237. Subsequence of A003015.
Cf. A059233.
Sequence in context: A064224 A069674 A003015 * A084142 A349745 A256814
KEYWORD
nonn,more
AUTHOR
Paul D. Hanna, Oct 27 2004
EXTENSIONS
a(7) from T. D. Noe, Jul 13 2005
STATUS
approved