OFFSET
0,3
COMMENTS
LINKS
T. D. Noe, Table of n, a(n) for n = 0..1000
EXAMPLE
a(3)=25 from the points of shapes 00 (1), 10 (4), 11 (4), 20 (4), 21 (8), 22 (4).
MATHEMATICA
Table[Sum[SquaresR[2, k], {k, 0, n^2 - 1}], {n, 0, 46}]
PROG
(Haskell)
a051132 n = length [(x, y) | x <- [-n..n], y <- [-n..n], x^2 + y^2 < n^2]
-- Reinhard Zumkeller, Jan 23 2012
CROSSREFS
KEYWORD
nonn,nice,easy
AUTHOR
Jostein Trondal (jostein.trondal(AT)protech.no)
EXTENSIONS
More terms from James A. Sellers
STATUS
approved