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 A056057 The largest square which divides n-th central binomial coefficient. 10
 1, 1, 1, 1, 1, 4, 1, 1, 9, 36, 1, 4, 4, 4, 9, 9, 1, 4, 1, 4, 4, 4, 1, 4, 100, 100, 900, 900, 36, 144, 9, 9, 9, 36, 25, 100, 100, 100, 9, 36, 4, 4, 4, 4, 900, 3600, 225, 900, 1764, 1764, 1764, 1764, 196, 784, 4, 4, 4, 16, 4, 16, 16, 16, 441, 441, 49, 196, 49, 196, 36, 36, 1, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A008833(A001405(n)). a(A046098(n)) = 1. MATHEMATICA Table[First@ Select[Reverse@ Divisors@ Binomial[n, Floor[n/2]], IntegerQ@ Sqrt@ # &], {n, 72}] (* Michael De Vlieger, Feb 18 2017 *) a[n_] := Times @@ (First[#]^(2*Floor[Last[#]/2]) & /@ FactorInteger[Binomial[n, Floor[n/2]]]); Array[a, 100] (* Amiram Eldar, Sep 06 2020 *) CROSSREFS Cf. A001405, A000188, A008833, A007913, A055229, A055231, A046098, A034974. Cf. A056056, A056058, A056059, A056060, A056061. Sequence in context: A219207 A157108 A056647 * A226234 A185027 A016520 Adjacent sequences:  A056054 A056055 A056056 * A056058 A056059 A056060 KEYWORD nonn AUTHOR Labos Elemer, Jul 26 2000 STATUS approved

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Last modified August 4 12:27 EDT 2021. Contains 346447 sequences. (Running on oeis4.)