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%I #10 Jan 07 2025 08:49:25
%S 2,6,-60,126,-32760,-262140,-3145716,2147483646,-4611686018427387900,
%T -2475880078570760549798248440,-1622592768292133633915780102881260,
%U -340282366920938463463374607431768211452
%N a(n) = A023900(n*A000396(n)).
%F Conjecture: a(n) = (-1)^(n+1)*A023900(n)*A023900(A000396(n)).
%t nn = 12; A023900[n_] := DivisorSum[n, MoebiusMu[#] # &]; Table[A023900[PerfectNumber[n]*n], {n, 1, nn}]
%Y Cf. A379724, A000396, A023900, A000668.
%K sign
%O 1,1
%A _Mats Granvik_, _Antti Karttunen_, Dec 31 2024