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A080918 Number of integer solutions to the equation 2x^2+y^2+32z^2=n. 5
1, 2, 2, 4, 2, 0, 4, 0, 2, 6, 0, 4, 4, 0, 0, 0, 2, 4, 6, 4, 0, 0, 4, 0, 4, 2, 0, 8, 0, 0, 0, 0, 4, 12, 8, 8, 10, 0, 12, 0, 4, 16, 0, 12, 12, 0, 0, 0, 8, 10, 14, 16, 0, 0, 16, 0, 8, 12, 0, 20, 0, 0, 0, 0, 6, 16, 16, 4, 16, 0, 8, 0, 6, 12, 0, 12, 12, 0, 0, 0, 8, 14, 8, 20, 0, 0, 20, 0, 4, 20, 0, 8, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..10000

J. B. Tunnell, A classical Diophantine problem and modular forms of weight 3/2, Invent. Math., 72 (1983), 323-334.

FORMULA

G.f.: theta_3(q) * theta_3(q^2) * theta_3(q^32).

PROG

(PARI) {a(n)=my(A); if(n<0, 0, A=x*O(x^n); polcoeff( eta(x^2+A)^3*eta(x^4+A)^3*eta(x^64+A)^5/ (eta(x+A)*eta(x^8+A)*eta(x^32+A)*eta(x^128+A))^2, n))}

CROSSREFS

a(2n-1)=A072069(n).

Cf. A000122 (theta_3(q)), A080917.

Sequence in context: A033715 A082564 A139093 * A033758 A033750 A033746

Adjacent sequences:  A080915 A080916 A080917 * A080919 A080920 A080921

KEYWORD

nonn

AUTHOR

Michael Somos, Feb 23 2003

STATUS

approved

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Last modified April 7 19:49 EDT 2020. Contains 333306 sequences. (Running on oeis4.)