%I #10 Sep 09 2022 02:31:06

%S 2,8,18,32,41,72,98,128,162,181,242,288,313,392,421,512,514,648,722,

%T 761,882,968,1058,1152,1201,1301,1458,1568,1466,1741,1922,2048,2178,

%U 2056,2381,2592,2594,2888,2817,3121,3202,3528,3698,3872,3789,4232,4418,4608,4802,4804,5101

%N a(n) is the position of the latest occurrence of n in A133388.

%F a(k) = 2*k^2 for k not in A009003.

%o (Python)

%o from sympy.solvers.diophantine.diophantine import diop_DN

%o def A356209(n):

%o for m in range(n**2<<1,0,-1):

%o if n==max((a for a, b in diop_DN(-1,m)),default=0):

%o return m # _Chai Wah Wu_, Sep 08 2022

%Y Cf. A000161, A001481, A009003, A356208.

%K nonn

%O 1,1

%A _Hugo Pfoertner_, Sep 07 2022