login
a(n) = n * Sum_{d|n} (binomial(n,d) / gcd(n,d)).
2

%I #5 Oct 26 2019 16:55:23

%S 1,6,12,44,30,252,56,856,846,3080,132,20616,182,49532,52110,237232,

%T 306,1227096,380,4106320,2470272,15525092,552,86092176,1328900,

%U 270424752,126624006,1157002616,870,5577100260,992,19572325728,6386892930

%N a(n) = n * Sum_{d|n} (binomial(n,d) / gcd(n,d)).

%F a(n) = n * A056045(n) = n * Sum_{d|n} (binomial(n, d) / gcd(n, d)).

%t f[n_] := Block[{d = Divisors[n]}, n*Plus @@ (Binomial[n, d])]; Table[ f[n], {n, 34}]

%Y Cf. A056045, A105861, A105862.

%K nonn

%O 1,2

%A _Robert G. Wilson v_, Apr 23 2005