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a(n) = Sum_{d|n} binomial(n,d)^d.
0

%I #10 Oct 08 2021 22:36:04

%S 1,3,4,41,6,8232,8,24010793,592714,1016255022068,12,

%T 622345952235575570,14,5608296349498479967477864,244217432525411634,

%U 752711194884611945714364093774417,18,1518219588672387062467026014355119245302660,20,46343145866349732399475841723455056148192256553403946

%N a(n) = Sum_{d|n} binomial(n,d)^d.

%F If p is prime, a(p) = 1 + p.

%t a[n_] := DivisorSum[n, Binomial[n, #]^# &]; Array[a, 20] (* _Amiram Eldar_, Oct 08 2021 *)

%o (PARI) a(n) = sumdiv(n, d, binomial(n, d)^d);

%Y Cf. A174464.

%K nonn

%O 1,2

%A _Seiichi Manyama_, Oct 08 2021