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A049474
a(n) = ceiling(n/sqrt(2)).
7
0, 1, 2, 3, 3, 4, 5, 5, 6, 7, 8, 8, 9, 10, 10, 11, 12, 13, 13, 14, 15, 15, 16, 17, 17, 18, 19, 20, 20, 21, 22, 22, 23, 24, 25, 25, 26, 27, 27, 28, 29, 29, 30, 31, 32, 32, 33, 34, 34, 35, 36, 37, 37, 38, 39, 39, 40, 41, 42, 42, 43, 44, 44, 45, 46, 46, 47
OFFSET
0,3
LINKS
MATHEMATICA
Table[Ceiling[n/Sqrt[2]], {n, 0, 50}] (* G. C. Greubel, Jul 06 2017 *)
PROG
(Haskell)
a049474 = ceiling . (/ sqrt 2) . fromIntegral
-- Reinhard Zumkeller, Jul 01 2015
(PARI) a(n)=if(n, sqrtint((n^2-1)\2)+1, 0) \\ Charles R Greathouse IV, Sep 02 2015
CROSSREFS
A099188(n) = 2*a(n).
Cf. A049472.
Sequence in context: A356988 A248186 A248183 * A076874 A127041 A173023
KEYWORD
nonn
STATUS
approved