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%I #14 Mar 06 2016 16:59:31
%S 1,4,12,40,140,816,5082,40800,363258,3632880,39916910,479052528,
%T 6227020956,87178936992,1307674429440,20922800222848,355687428096272,
%U 6402373892575992,121645100408832342,2432902011892837920
%N Row sums of the table A047916.
%H Harry J. Smith, <a href="/A064649/b064649.txt">Table of n, a(n) for n=1..100</a>
%F a(n) = Sum_{d|n} phi(n/d)*(n/d)^d*d!. - _Michel Marcus_, Mar 06 2016
%p A064649 := proc(n) local d, s; s := 0; for d in divisors(n) do s := s + phi(n/d)*(n/d)^d*d!; od; RETURN(s); end;
%t a[n_] := DivisorSum[n, EulerPhi[n/#]*(n/#)^#*#!&]; Array[a, 20] (* _Jean-François Alcover_, Mar 06 2016 *)
%o (PARI) { for (n=1, 100, a=0; v=divisors(n); for (i=1, length(v), d=v[i]; a+=eulerphi(n/d)*(n/d)^d*d!); write("b064649.txt", n, " ", a) ) } \\ _Harry J. Smith_, Sep 21 2009
%o (PARI) a(n) = sumdiv(n, d, eulerphi(n/d)*(n/d)^d*d!); \\ _Michel Marcus_, Mar 06 2016
%o (Haskell)
%o a064649 = sum . a047916_row -- _Reinhard Zumkeller_, Mar 19 2014
%Y Also n*A061417[n]. Cf. A047918, A002619.
%K nonn
%O 1,2
%A _Antti Karttunen_, Oct 04 2001
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