login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A211645 Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2>=2n. 2

%I #5 Dec 04 2016 19:46:27

%S 0,1,7,26,60,118,206,332,495,709,974,1299,1693,2159,2696,3321,4036,

%T 4847,5757,6781,7913,9165,10543,12053,13704,15498,17437,19538,21795,

%U 24220,26822,29607,32572,35735,39087,42643,46418,50409,54609,59041

%N Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2>=2n.

%C For a guide to related sequences, see A211422.

%t t = Compile[{{n, _Integer}}, Module[{s = 0},

%t (Do[If[w^2 + x^2 + y^2 >= 2 n, s = s + 1],

%t {w, 1, #}, {x, 1, #}, {y, 1, #}] &[n]; s)]];

%t Map[t[#] &, Range[0, 80]] (* A211645 *)

%t (* _Peter J. C. Moses_, Apr 13 2012 *)

%Y Cf. A211422.

%K nonn

%O 0,3

%A _Clark Kimberling_, Apr 18 2012

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 23 15:20 EDT 2024. Contains 371916 sequences. (Running on oeis4.)