A117694 - OEIS

%I #7 Jul 23 2023 06:00:25

%S 1,3,15,130,1565,23331,411775,8388612,193710249,5000000005,

%T 142655835311,4458050224134,151437553296133,5556003412779015,

%U 218946945190429695,9223372036854775816,413620130943168382097,19673204037648268787721

%N a(n) = (n^n + n)/2.

%H G. C. Greubel, <a href="/A117694/b117694.txt">Table of n, a(n) for n = 1..380</a>

%F a(n) = (n^n + n)/2.

%F a(n) = A066068(n)/2, for n > 0.

%F E.g.f.: (1/2)*(x*exp(x) - LambertW(-x)/(1 + LambertW(-x))). - _G. C. Greubel_, Jul 23 2023

%t Table[n^n+n, {n,30}]/2

%o (Magma) [(n+n^n)/2: n in [1..30]]; // _G. C. Greubel_, Jul 23 2023

%o (SageMath) [(n+n^n)/2 for n in range(1,31)] # _G. C. Greubel_, Jul 23 2023

%Y Cf. A066068.

%K nonn

%O 1,2

%A _Alexander Adamchuk_, Apr 12 2006