if a^2 belongs to an arithmetic progression with ratio m (and m is a positive integer (see Steve Herman and broll)
Then the squares of a+m, a+2m, ... a+km ... belong to the sequence
(a+km)^2= a^2+m*(mk^2+2ak)
========
Ramdom ex:
a^2=36 m=13 k=5
(6+13*5)^2=71^2=5041=36+385*13
Edited on March 28, 2018, 2:13 pm

Posted by armando
on 20180328 12:46:26 