A373885 Number of lattice points inside or on the 7-dimensional hypersphere x_1^2 + x_2^2 + x_3^2 + x_4^2 + x_5^2 + x_6^2 + x_7^2 = 10^n.
15, 16859, 48218513, 149732983675, 472579187185537, 1494134816265585397, 4724776275561584896709, 14941025134674593046033085
Offset: 0
Programs
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PARI
b(k, n) = my(q='q+O('q^(n+1))); polcoef((eta(q^2)^5/(eta(q)^2*eta(q^4)^2))^k/(1-q), n); a(n) = b(7, 10^n);
Formula
a(n) = A341396(10^n).
Extensions
a(7) from Chai Wah Wu, Jun 23 2024