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A078183 Number of solutions to x^2 + y^2 + z^2 < n^2; number of lattice points inside a sphere of radius n. 1
0, 1, 27, 93, 251, 485, 895, 1365, 2103, 2969, 4139, 5497, 7123, 9093, 11459, 13997, 17071, 20377, 24303, 28545, 33371, 38641, 44395, 50733, 57747, 65117, 73447, 82201, 91911, 101769, 112931, 124289, 137059, 150165, 164415, 179309, 195167 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..36.

FORMULA

a(n) = A000605(n) - A016725(n)

MATHEMATICA

s = 0; Table[s = s + Sum[SquaresR[3, k], {k, (n - 1)^2, n^2 - 1}], {n, 0, 50}]

CROSSREFS

Cf. A000605, A016725.

Sequence in context: A286192 A101100 A226359 * A072252 A154041 A233156

Adjacent sequences:  A078180 A078181 A078182 * A078184 A078185 A078186

KEYWORD

nonn

AUTHOR

T. D. Noe, Nov 21 2002

STATUS

approved

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Last modified May 25 22:51 EDT 2022. Contains 354073 sequences. (Running on oeis4.)