%I #24 Apr 15 2023 14:14:47
%S 1,2,6,12,60,180,1152,2520,7560,37332,415800,1247400,16118932,
%T 112918900,564876900,1109481408,17645365584,57890359152,1099944846000,
%U 5468570553600,37559092302400,421791599312500,9256378099515120,29207007622737652,146100174169950000,1880759745476519040,5589847741506645552,39852571442073216768
%N Euler's totient of A104365(n) = A104350(n) + 1.
%H Max Alekseyev, <a href="/A104371/b104371.txt">Table of n, a(n) for n = 1..158</a> (terms 1..76 terms from Amiram Eldar, terms 142..151 from Tyler Busby)
%H Reinhard Zumkeller, <a href="/A104350/a104350.txt">Products of largest prime factors of numbers <= n</a>
%F a(n) = A000010(A104365(n));
%F a(p) = A104350(p) for primes p.
%t a[n_] := EulerPhi[1 + Product[FactorInteger[k][[-1, 1]], {k, 1, n}]]; Array[a, 76] (* _Amiram Eldar_, Feb 12 2020 *)
%Y Cf. A000010, A104350, A104363, A104365, A104366, A104367, A104368, A104369, A104370, A104372.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Mar 06 2005
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