A121855 a(n) = ceiling(Pi*sqrt(n)).

0, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 13, 14, 14, 15, 15, 15, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24, 24, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 27, 27, 27

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000 (indices changed and term 1000 added by Ivan Panchenko)

Mathematica

Table[Ceiling[Pi Sqrt[n]], {n, 0, 100}] (* Vincenzo Librandi, Feb 21 2013 *)

Crossrefs

Cf. A121275, A121276.

Sequence in context: A102691 A014553 A227422 * A239440 A248355 A178053

Adjacent sequences: A121852 A121853 A121854 * A121856 A121857 A121858

Keyword

nonn,easy

Author

Mohammad K. Azarian, Aug 30 2006

Extensions

Offset corrected by Ivan Panchenko, Nov 13 2013

Status

approved