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A029714
a(n) = Sum_{k divides 3^n} S(k), where S is the Kempner function A002034.
1
1, 4, 10, 19, 28, 40, 55, 73, 91, 112, 136, 163, 190, 217, 247, 280, 316, 352, 391, 433, 478, 523, 571, 622, 676, 730, 784, 841, 901, 964, 1027, 1093, 1162, 1234, 1306, 1381, 1459, 1540, 1621, 1702, 1783, 1867, 1954, 2044, 2134, 2227, 2323, 2422, 2521, 2623
OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n-1} A002034(3^k). - Alois P. Heinz, Sep 14 2008
MAPLE
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
MATHEMATICA
S[n_] := S[n] = Module[{k=1}, While[True, If[Divisible[k!, n], Return[k], k++] ] ];
a[n_] := S /@ Divisors[3^n] // Total;
a /@ Range[0, 49] (* Jean-François Alcover, Nov 17 2020 *)
CROSSREFS
Sequence in context: A145731 A162958 A307395 * A348239 A062198 A050858
KEYWORD
nonn
AUTHOR
Norbert Hungerbuhler (buhler(AT)math.ethz.ch)
EXTENSIONS
More terms from Alois P. Heinz, Sep 14 2008
STATUS
approved