The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A175362 Number of integer pairs (x,y) satisfying |x|^3 + |y|^3 = n, -n <= x,y <= n. 5
 1, 4, 4, 0, 0, 0, 0, 0, 4, 8, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Cube variant of A004018. Obviously, a(n) must be 4*k, for k >= 0, n > 0. - Altug Alkan, Apr 09 2016 From Robert Israel, Jan 26 2017: (Start) a(k^3*n) >= a(n) for k >= 1. a(n) >= 16 for n in A001235. a(A011541(n)) >= 8*n. (End) LINKS Robert Israel, Table of n, a(n) for n = 0..10000 FORMULA G.f.: ( 1 + 2 * Sum_{j>=1} x^(j^3) )^2. a(n^3) = 4 for n > 0. - Altug Alkan, Apr 09 2016 EXAMPLE a(2) = 4 counts (x,y) = (-1,1), (1,1), (-1,-1) and (1,-1). a(9) = 8 counts (x,y) = (-2,-1), (-2,1), (-1,-2), (-1,2), (1,-2), (1,2), (2,-1) and (2,1). MAPLE N:= 200: # to get a(0)..a(N) G:= (1+2*add(x^(j^3), j=1..floor(N^(1/3))))^2: seq(coeff(G, x, j), j=0..N); # Robert Israel, Jan 26 2017 CROSSREFS Cf. A001235, A010057, A011541, A025446, A025455, A025464, A025468, A121980. Sequence in context: A197243 A175372 A069191 * A189973 A282866 A098445 Adjacent sequences:  A175359 A175360 A175361 * A175363 A175364 A175365 KEYWORD nonn AUTHOR R. J. Mathar, Apr 24 2010 EXTENSIONS Invalid claim that belonged to A004018 removed by R. J. Mathar, Apr 24 2010 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.

Last modified May 7 05:10 EDT 2021. Contains 343636 sequences. (Running on oeis4.)