login
a(n) = greatest positive r <= n, such that the origin-centered sphere of radius sqrt(r) touches A071342(n) lattice points.
4

%I #5 Oct 19 2017 03:14:02

%S 1,2,9,14,21,29,41,62,74,89,101,134,161,194,209,230,269,314,341,374,

%T 425,446,521,569,614,629,689,761,794,866,941,941,941,1154,1154,1286,

%U 1361,1361,1454,1454,1634,1634,1781,1889,1889,2054,2141,2246,2246

%N a(n) = greatest positive r <= n, such that the origin-centered sphere of radius sqrt(r) touches A071342(n) lattice points.

%e a(4)=21 because the largest sphere with radius <= 4 to touch A071342(4)=48 points has radius sqrt(21).

%o (FORTRAN) See A071339.

%Y Cf. A071339-A071347.

%K easy,nonn

%O 1,2

%A _Hugo Pfoertner_, May 22 2002

%E Edited by _Don Reble_, Nov 06 2005