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%I A064451 #19 Nov 04 2019 11:08:39
%S A064451 1,1,2,2,4,8,24,24,72,288,240,240,1440,2880,2880,11520,23040,46080,
%T A064451 207360,276480,82944,829440,2280960,9123840,15206400,60825600,
%U A064451 273715200,1642291200,766402560,7664025600,1916006400,1277337600
%N A064451 LCM of totients of binomial coefficients C(n,j), j = 0..n.
%H A064451 Harry J. Smith, <a href="/A064451/b064451.txt">Table of n, a(n) for n = 1..200</a>
%e A064451 For n=4, the binomial coefficients C(4,j) are 1, 4, 6, 4, and 1. The totients are 1, 2, 2, 2, and 1.  So a(4) = lcm of 1, 2, 2, 2, 1 = 2. - _Michael B. Porter_, Jun 25 2018
%t A064451 Table[LCM@@Table[EulerPhi[Binomial[n,j]],{j,0,n}],{n,40}] (* _Harvey P. Dale_, Nov 04 2019 *)
%o A064451 (PARI) { for (n=1, 200, a=1; for (j=0, n, a=lcm(a, eulerphi(binomial(n, j)))); write("b064451.txt", n, " ", a) ) } \\ _Harry J. Smith_, Sep 14 2009
%o A064451 (PARI) a(n) = lcm(vector(n+1, k, eulerphi(binomial(n, k-1)))); \\ _Michel Marcus_, Jun 24 2018
%Y A064451 Cf. A002944 (see 1st comment there).
%K A064451 nonn
%O A064451 1,3
%A A064451 _Labos Elemer_, Oct 02 2001
%E A064451 Previous Mathematica program replaced by _Harvey P. Dale_, Nov 04 2019

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