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%I #12 Dec 02 2021 13:01:51
%S 1,1,1,1,1,3,1,1,1,10,1,3,1,21,10,1,1,3,1,10,35,55,1,3,1,78,1,21,1,10,
%T 1,1,165,136,21,3,1,171,286,10,1,21,1,55,10,253,1,3,1,10,680,78,1,3,
%U 462,21,969,406,1,10,1,465,35,1,1287,55,1,136,1771,21,1,3,1,666,10
%N Binomial(greatest prime factor of n, smallest prime factor of n).
%H Antti Karttunen, <a href="/A080214/b080214.txt">Table of n, a(n) for n = 1..65537</a>
%t a[n_] := With[{f = FactorInteger[n]}, Binomial[f[[-1, 1]], f[[1, 1]]]];
%t Array[a, 100] (* _Jean-François Alcover_, Dec 02 2021 *)
%o (PARI) A080214(n) = if(1==n,n,my(f = factor(n), lpf = f[1, 1], gpf = f[#f~, 1]); binomial(gpf,lpf)); \\ _Antti Karttunen_, Sep 06 2018
%Y Cf. A006530, A020639, A080215, A080211.
%K nonn,look
%O 1,6
%A _Reinhard Zumkeller_, Feb 06 2003
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