A071347 - OEIS

%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