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A181550 T(n,k) = floor(n/k)*A181549(k), triangle read by rows.

%I A181550 #13 Feb 05 2014 06:43:56
%S A181550 1,2,3,3,3,4,4,6,4,5,5,6,4,5,6,6,9,8,5,6,12,7,9,8,5,6,12,8,8,12,8,10,
%T A181550 6,12,8,10,9,12,12,10,6,12,8,10,11,10,15,12,10,12,12,8,10,11,18,11,15,
%U A181550 12,10,12,12,8,10,11,18,12,12,18,16,15,12,24,8,10,11,18,12,20
%N A181550 T(n,k) = floor(n/k)*A181549(k), triangle read by rows.
%C A181550 A181549(n) = sum{k|n} k mu_2(n/k), a variant of Euler's phi function relative to the Moebius function of order 2.
%H A181550 Peter Luschny, Sequences related to <a href="http://www.oeis.org/wiki/User:Peter_Luschny/EulerTotient">Euler's totient</a> function.
%e A181550 1
%e A181550 2, 3
%e A181550 3, 3, 4
%e A181550 4, 6, 4, 5
%e A181550 5, 6, 4, 5, 6
%e A181550 6, 9, 8, 5, 6, 12
%e A181550 7, 9, 8, 5, 6, 12, 8
%e A181550 8, 12, 8, 10, 6, 12, 8, 10
%p A181550 A181550 := (n,k) -> iquo(n,k)*A181549(k);
%t A181550 mu2[1] = 1; mu2[n_] := Sum[Boole[Divisible[n, d^2]]*MoebiusMu[n/d^2]*MoebiusMu[n/d], {d, Divisors[n]}]; A181549[n_] := Sum[k*mu2[n/k], {k, Divisors[n]}]; t[n_, k_] := Floor[n/k]*A181549[k]; Table[t[n, k], {n, 1, 12}, {k, 1, n}] // Flatten (* _Jean-François Alcover_, Feb 05 2014 *)
%Y A181550 Cf. A130212, A181549.
%K A181550 nonn,tabl
%O A181550 1,2
%A A181550 _Peter Luschny_, Oct 30 2010