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A055411 Number of points in Z^5 of norm <= n.

%I A055411 #29 Jun 24 2024 10:51:16
%S A055411 1,11,221,1343,5913,16875,42205,89527,176377,313259,532509,853399,
%T A055411 1322921,1961211,2846933,4005143,5554265,7491355,9977557,13065527,
%U A055411 16907817,21524019,27179909,33921671,42036401,51452803,62664773
%N A055411 Number of points in Z^5 of norm <= n.
%H A055411 Chai Wah Wu, <a href="/A055411/b055411.txt">Table of n, a(n) for n = 0..10000</a> (terms 0..500 from Andrew Howroyd)
%F A055411 a(n) = A122510(5,n^2). - _R. J. Mathar_, Apr 21 2010
%F A055411 a(n) = [x^(n^2)] theta_3(x)^5/(1 - x), where theta_3() is the Jacobi theta function. - _Ilya Gutkovskiy_, Apr 14 2018
%t A055411 t[d_, n_] := t[d, n] = t[d, n - 1] + SquaresR[d, n]; t[d_, 0] = 1;
%t A055411 a[n_] := t[5, n^2];
%t A055411 a /@ Range[0, 100] (* _Jean-François Alcover_, Sep 27 2019, after _R. J. Mathar_ *)
%o A055411 (Python)
%o A055411 # uses Python code for A046895
%o A055411 def A055411(n): return A046895(m:=n**2)+(sum(A046895(m-k**2) for k in range(1,n+1))<<1) # _Chai Wah Wu_, Jun 23 2024
%Y A055411 Column k=5 of A302997.
%Y A055411 Cf. A122510.
%K A055411 nonn
%O A055411 0,2
%A A055411 _David W. Wilson_