|
|
A000801
|
|
a(n) = Sum_{k = 1..n} floor(2^k / k).
(Formerly M1015 N0381)
|
|
2
|
|
|
2, 4, 6, 10, 16, 26, 44, 76, 132, 234, 420, 761, 1391, 2561, 4745, 8841, 16551, 31114, 58708, 111136, 211000, 401650, 766372, 1465422, 2807599, 5388709, 10359735, 19946715, 38459505, 74250899, 143524565, 277742293, 538043341, 1043333611, 2025040421
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
REFERENCES
|
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
LINKS
|
|
|
MAPLE
|
A000801 := proc(n) local k; sum(floor(2^k/k), k=1..n); end;
|
|
MATHEMATICA
|
Table[Sum[Floor[2^k/k], {k, n}], {n, 30}] (* T. D. Noe, Jun 20 2012 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|