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A211645 Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2>=2n. 2
0, 1, 7, 26, 60, 118, 206, 332, 495, 709, 974, 1299, 1693, 2159, 2696, 3321, 4036, 4847, 5757, 6781, 7913, 9165, 10543, 12053, 13704, 15498, 17437, 19538, 21795, 24220, 26822, 29607, 32572, 35735, 39087, 42643, 46418, 50409, 54609, 59041 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

For a guide to related sequences, see A211422.

LINKS

Table of n, a(n) for n=0..39.

MATHEMATICA

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

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

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

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

(* Peter J. C. Moses, Apr 13 2012 *)

CROSSREFS

Cf. A211422.

Sequence in context: A206481 A049453 A231888 * A171340 A046433 A128972

Adjacent sequences:  A211642 A211643 A211644 * A211646 A211647 A211648

KEYWORD

nonn

AUTHOR

Clark Kimberling, Apr 18 2012

STATUS

approved

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Last modified February 23 10:11 EST 2020. Contains 332160 sequences. (Running on oeis4.)