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Let b(n) = A048273(n) = maximal number of prime factors of C(n,k) for k=0..n; sequence gives smallest value of k achieving b(n).
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%I #12 Aug 02 2017 10:27:33

%S 0,1,1,2,2,1,2,4,3,4,4,6,6,5,4,8,8,6,6,8,8,8,8,10,5,6,12,10,10,9,10,

%T 12,12,16,15,16,16,18,18,20,20,18,18,20,16,13,16,19,20,15,20,17,18,21,

%U 24,20,21,21,21,28,29,21,21,32,32,28,29,32,32,32,28,28,29,32,32,32,35,32

%N Let b(n) = A048273(n) = maximal number of prime factors of C(n,k) for k=0..n; sequence gives smallest value of k achieving b(n).

%H Michael De Vlieger, <a href="/A048299/b048299.txt">Table of n, a(n) for n = 1..1000</a>

%e For n = 50, the number of distinct prime factors of C(50, k) can be 0,2,3,4,5,6,7,8,9,10. The maximum is reached at several positions k=15,17,...,33,35. Thus a(50) = 15, far from the central C(50, 25).

%t Table[Min@ MaximalBy[Range[0, n], PrimeNu@ Binomial[n, #] &], {n, 78}] (* _Michael De Vlieger_, Aug 01 2017 *)

%Y Cf. A001221, A048273, A001405, A048571.

%K nonn

%O 1,4

%A _Labos Elemer_