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%I #5 Oct 19 2017 03:14:02
%S 1,3,9,15,18,30,42,54,78,90,114,126,150,186,210,210,270,270,330,390,
%T 390,450,510,570,594,630,630,750,810,882,930,990,1050,1050,1170,1170,
%U 1350,1386,1470,1530,1650,1710,1710,1890,1890,1890,1890,2250,2310
%N a(n) = greatest positive r <= n, such that the origin-centered 4d-sphere of radius sqrt(r) touches A071345(n) lattice points.
%e a(4)=15 because the largest 4d-sphere with radius <= 4 to touch A071345(4)=192 points has radius sqrt(15).
%o (FORTRAN) See A071339.
%Y Cf. A071339-A071346.
%K easy,nonn
%O 1,2
%A _Hugo Pfoertner_, May 22 2002
%E Edited by _Don Reble_, Nov 06 2005