MathDB

a

is a

2000

digit natural number of the form

a=2(A)99…99(B)(C)

expressed in base

10

a

is not a multiple of

10

, and

2(A)+(B)(C)=99

a=2899..9971

is a possible example of

a

b

is a number you earn when you write the digits of

a

in a reverse order(Writing the digits of some number in a reverse order means like reordering

1234

into

4321

). Find every positive integer

a

that makes

ab

a square number.

Problem Statement