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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
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
KEYWORD
nonn
AUTHOR
Michael Somos, Feb 23 2003
STATUS
approved

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Last modified June 14 08:28 EDT 2024. Contains 373393 sequences. (Running on oeis4.)