A087672 - OEIS

%I #2 Oct 12 2013 15:31:16

%S 891,1485,1584,2376,3168,4455,4752,89991,95931,101871,107811,149985,

%T 155925,159984,161865,167805,167904,175824,183744,191664,239976,

%U 247896,255816,263736,271656,319968,327888,335808,343728,351648,449955,479655

%N n = k^2 - (reversal of k)^2 for two different values of k.

%C Each n is a multiple of 99. The first few pairs for k: (30,54) (41,87) (40,53) (51,75) (62,97) (72,96) (71,84) (300,504) (310,534) (320,564) (330,594) (401,807) (411,837) (400,503) (421,867) (431,897) (410,523) (420,543) (430,563) (440,583).

%e 2376 = 51^2 - 15^2 = 75^2 - 57^2; 161865 = 421^2 - 124^2 = 867^2 - 768^2

%K nonn

%O 0,1

%A _Paul Lusch_, Sep 26 2003