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A084888 Number of partitions of n^3 into two squares>0. 5
0, 0, 1, 0, 0, 2, 0, 0, 1, 0, 2, 0, 0, 2, 0, 0, 0, 2, 1, 0, 2, 0, 0, 0, 0, 3, 2, 0, 0, 2, 0, 0, 1, 0, 2, 0, 0, 2, 0, 0, 2, 2, 0, 0, 0, 2, 0, 0, 0, 0, 4, 0, 2, 2, 0, 0, 0, 0, 2, 0, 0, 2, 0, 0, 0, 8, 0, 0, 2, 0, 0, 0, 1, 2, 2, 0, 0, 0, 0, 0, 2, 0, 2, 0, 0, 8, 0, 0, 0, 2, 2, 0, 0, 0, 0, 0, 0, 2, 1, 0, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,6

COMMENTS

a(A050804(n)) = 1.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Diophantine Equation: 2nd Powers.

Reinhard Zumkeller, Illustration for A084888 and A000404

FORMULA

a(n) = A025426(A000578(n)).

EXAMPLE

n=100: 100^3 = 1000000 = 960^2 + 280^2 = 936^2 + 352^2 = 800^2 + 600^2, therefore a(100)=3.

PROG

(Haskell)

a084888 = a025426 . a000578  -- Reinhard Zumkeller, Jul 18 2012

(PARI) a(n)=my(f=factor(n^3)); (prod(i=1, #f~, if(f[i, 1]%4==1, f[i, 2]+1, f[i, 2]%2==0||f[i, 1]<3))-issquare(n)+1)\2 \\ Charles R Greathouse IV, May 18 2016

CROSSREFS

Cf. A000404, A063725, A000578, A000290.

Sequence in context: A321912 A092303 A063725 * A091400 A129448 A239003

Adjacent sequences:  A084885 A084886 A084887 * A084889 A084890 A084891

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 10 2003

STATUS

approved

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Last modified June 24 21:16 EDT 2019. Contains 324337 sequences. (Running on oeis4.)