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%I #14 Nov 17 2020 08:54:21
%S 1,4,10,19,28,40,55,73,91,112,136,163,190,217,247,280,316,352,391,433,
%T 478,523,571,622,676,730,784,841,901,964,1027,1093,1162,1234,1306,
%U 1381,1459,1540,1621,1702,1783,1867,1954,2044,2134,2227,2323,2422,2521,2623
%N a(n) = Sum_{k divides 3^n} S(k), where S is the Kempner function A002034.
%F a(n) = Sum_{k=0..n-1} A002034(3^k). - _Alois P. Heinz_, Sep 14 2008
%p s:= proc(n) local m; m:= 1; while not type(m!/n, integer) do m:= m+1 od; m end: a:= n-> add(s(3^k), k=0..n-1): seq(a(n), n=1..70); # _Alois P. Heinz_, Sep 14 2008
%t S[n_] := S[n] = Module[{k=1}, While[True, If[Divisible[k!, n], Return[k], k++] ] ];
%t a[n_] := S /@ Divisors[3^n] // Total;
%t a /@ Range[0, 49] (* _Jean-François Alcover_, Nov 17 2020 *)
%Y Cf. A029715, A002034.
%K nonn
%O 0,2
%A Norbert Hungerbuhler (buhler(AT)math.ethz.ch)
%E More terms from _Alois P. Heinz_, Sep 14 2008
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