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%I #8 Mar 08 2014 12:41:39
%S 0,0,1,1,2,2,2,3,4,0,4,5,2,4,6,6,0,8,0,9,8,9,10,11,4,5,10,0,10,11,2,
%T 10,0,1,16,3,0,4,18,18,4,9,10,18,20,12,18,20,0,0,0,1,16,21,18,10,0,21,
%U 22,23,28,29,30,9,0,1,2,3,32,33,6,35,0,9,32,10,36
%N Index of last squarefree number in the first half of row n of Pascal's triangle.
%C The first squarefree binomial coefficient in every row is at position 0. Sequence A048279 lists the rows n for which a(n) = 0.
%H T. D. Noe, <a href="/A238892/b238892.txt">Table of n, a(n) for n = 0..10000</a>
%t Table[Position[Binomial[n, Range[0, n/2]], _?(SquareFreeQ[#] &)][[-1,1]] - 1, {n, 0, 100}]
%Y Cf. A048279 (positions of zeros).
%Y Cf. A238337 (number of distinct squarefree numbers in row n).
%Y Cf. A238891 (last squarefree number in the first half of row n).
%K nonn
%O 0,5
%A _T. D. Noe_, Mar 06 2014