Find infinitely many triples (a,b,c) of distinct positive integers such that a, b, c are in arithmetic progression and ab+1,bc+1,ca+1 are perfect squares.
(In reply to
a partial list of infinity by Dej Mar)
It's not possible to list them all, of course, but there is a formula that generates the members of your list.
The recurrence for each triple (a(n),b(n),c(n)) can be written as
a(n)=4*a(n1)a(n2)
b(n)=2*a(n+1)
c(n)=a(n+2)
but I don't have proof of this yet. (Nor do I have proof that there aren't others not covered here.)

Posted by Jer
on 20180326 09:52:43 