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%I #13 May 11 2023 08:47:20
%S 1,1,1,6,1,1,1,28,84,1,1,924,1,1,1,120,1,18564,1,184756,1,1,1,134596,
%T 53130,1,2925,40116600,1,1,1,496,1,1,1,1947792,1,1,1,847660528,1,1,1,
%U 2104098963720,344867425584,1,1,12271512,85900584,10272278170,1
%N Binomial coefficient ( n, squarefree kernel(n) ).
%C a(n)=1 iff n is squarefree.
%H Robert Israel, <a href="/A073354/b073354.txt">Table of n, a(n) for n = 1..3315</a>
%F a(n) = binomial(n, A007947(n)).
%p f:= proc(n) local k;
%p k:= convert(numtheory:-factorset(n),`*`);
%p binomial(n,k)
%p end proc:
%p map(f, [$1..60]); # _Robert Israel_, May 07 2021
%t a[n_] := Binomial[n, Times @@ FactorInteger[n][[All, 1]]];
%t Table[a[n], {n, 1, 60}] (* _Jean-François Alcover_, May 11 2023 *)
%Y Cf. A007947, A005117, A073353, A066503, A064549, A003557.
%K nonn,look
%O 1,4
%A _Reinhard Zumkeller_, Jul 29 2002