%I #7 Aug 06 2024 02:07:24
%S 1,1,0,3,-7,22,-36,14,-44,-29,-91,1525,-1692,-1686,109,-1246,534,2818,
%T -5769,1034,-5042,-16561,5185,315777,-321633,-338860,5749,-319896,
%U 318256,441483,-804427,-801359,330352,-1196712,810803,8888500,-9692338,-9803611,814401,-8682691
%N a(n) = Sum_{k<=n} A007955(k) * A008683(n-k+1) = Sum_{k<=n} A007955(k) * mu(n-k+1), where A007955(m) = product of divisors of m.
%e For n = 4, A007955(n) = b(n): a(4) = b(1)*mu(4) + b(2)*mu(3) + b(3)* mu(2) + b(4)*mu(1) = 1*0 + 2*(-1) + 3*(-1) + 8*1 = 3.
%t a[n_] := Sum[k^(DivisorSigma[0, k]/2) * MoebiusMu[n-k+1], {k, 1, n}]; Array[a, 50] (* _Amiram Eldar_, Aug 06 2024 *)
%Y Cf. A007955, A008683.
%K sign
%O 1,4
%A _Jaroslav Krizek_, Apr 02 2010
%E More terms from _Amiram Eldar_, Aug 06 2024
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