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A049472
a(n) = floor(n/sqrt(2)).
23
0, 0, 1, 2, 2, 3, 4, 4, 5, 6, 7, 7, 8, 9, 9, 10, 11, 12, 12, 13, 14, 14, 15, 16, 16, 17, 18, 19, 19, 20, 21, 21, 22, 23, 24, 24, 25, 26, 26, 27, 28, 28, 29, 30, 31, 31, 32, 33, 33, 34, 35, 36, 36, 37, 38, 38, 39, 40, 41, 41, 42, 43, 43, 44, 45, 45, 46, 47
OFFSET
0,4
COMMENTS
For n > 0: A006337(n) = number of repeating n's. - Reinhard Zumkeller, Jul 04 2015
LINKS
MAPLE
A049472:=n->floor(n/sqrt(2)): seq(A049472(n), n=0..100); # Wesley Ivan Hurt, Jun 25 2016
MATHEMATICA
Floor[Range[0, 70]/Sqrt[2]] (* Harvey P. Dale, Aug 22 2011 *)
PROG
(Magma) [Floor(n/Sqrt(2)): n in [0..70] ]; // Vincenzo Librandi, Aug 23 2011
(Haskell)
a049472 = floor . (/ sqrt 2) . fromIntegral
-- Reinhard Zumkeller, Jul 04 2015
(PARI) a(n)=sqrtint(n^2\2) \\ Charles R Greathouse IV, Sep 02 2015
CROSSREFS
First differences give A080764.
Sequence in context: A306726 A188511 A064488 * A368131 A125229 A213855
KEYWORD
nonn,easy
AUTHOR
STATUS
approved