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A000799
a(n) = floor(2^n / n).
(Formerly M0239 N0082)
22
2, 2, 2, 4, 6, 10, 18, 32, 56, 102, 186, 341, 630, 1170, 2184, 4096, 7710, 14563, 27594, 52428, 99864, 190650, 364722, 699050, 1342177, 2581110, 4971026, 9586980, 18512790, 35791394, 69273666, 134217728, 260301048, 505290270, 981706810, 1908874353
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
FORMULA
Sum_{n>=1} 1/a(n) = A193359. - Amiram Eldar, Apr 03 2021
MAPLE
seq(floor(2^n/n), n=1..40); # Muniru A Asiru, Oct 20 2018
MATHEMATICA
Table[Quotient[2^n, n], {n, 60}] (* Vladimir Joseph Stephan Orlovsky, May 07 2011 *)
PROG
(PARI) a(n)=1<<n\n
(Magma) [2^n div n : n in [1..40]]; // Vincenzo Librandi, Oct 14 2018
(GAP) List([1..40], n->Int(2^n/n)); # Muniru A Asiru, Oct 20 2018
(Python) for n in range(1, 40): print(int(2**n / n), end=", ") # Stefano Spezia, Oct 20 2018
CROSSREFS
KEYWORD
nonn,easy
STATUS
approved

  NODES
orte 1
see 1
Story 1