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Number of points in N^n of norm <= 4.
2

%I #11 Sep 29 2019 20:23:49

%S 1,5,17,54,165,482,1319,3390,8262,19250,43154,93601,197381,406200,

%T 817954,1614348,3126068,5943728,11103912,20396957,36869790,65637607,

%U 115178814,199377387,340708159,575150851,959691775,1583660542

%N Number of points in N^n of norm <= 4.

%H Andrew Howroyd, <a href="/A055419/b055419.txt">Table of n, a(n) for n = 0..1000</a>

%F Empirical g.f.: (11*x^16 -164*x^15 +936*x^14 -2841*x^13 +5310*x^12 -6697*x^11 +6044*x^10 -3984*x^9 +1734*x^8 -75*x^7 -741*x^6 +827*x^5 -539*x^4 +235*x^3 -68*x^2 +12*x -1) / (x -1)^17. - _Colin Barker_, Jul 07 2013

%Y Row n=4 of A302998.

%K nonn

%O 0,2

%A _David W. Wilson_