login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A182009 a(n) = ceiling(sqrt(2n*log(2))+(3-2*log(2))/6). 5
2, 2, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence approximates the sequence of solutions to the Birthday Problem, A033810. The two sequences agree for almost all n, i.e., on a set of integers n with density 1.

LINKS

Gheorghe Coserea, Table of n, a(n) for n = 1..10000

D. Brink, A (probably) exact solution to the Birthday Problem, Ramanujan Journal, 2012, pp 223-238.

MAPLE

seq(ceil((2*n*log(2))^(1/2) + (3-2*log(2))/6), n=1..1000); # Robert Israel, Aug 23 2015

MATHEMATICA

Table[Ceiling[Sqrt[2 n Log[2] + (3 - 2 Log[2])/6]], {n, 82}] (* Michael De Vlieger, Aug 24 2015 *)

PROG

(PARI)

a(n) = { ceil((2*n*log(2))^(1/2) + (3-2*log(2))/6) };

apply(n->a(n), vector(84, i, i))  \\ Gheorghe Coserea, Aug 23 2015

CROSSREFS

Approximates A033810.

Sequence in context: A036042 A162988 A143824 * A034463 A259899 A071996

Adjacent sequences:  A182006 A182007 A182008 * A182010 A182011 A182012

KEYWORD

nonn

AUTHOR

David Brink, Apr 06 2012

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 16 05:56 EDT 2019. Contains 328046 sequences. (Running on oeis4.)