Dudley, Underwood  <br/><br/>
Elementary Number Theory /  
Underwood Dudley 
 - USA  Freeman and company  1969 
 - vii, 262p. 
<br/><br/>Integers (Page-1), Unique Factorization (Page-10), Linear Diophantine Equations (Page-20), Congruences  (Page-27), Linear Congruences (Page-34), Fermat's and Wilson's Theorems  (Page-42), The Divisors of an Integer  (Page-50), Perfect Numbers  (Page-57), Euler's Theorem and Function  (Page-63), Primitive Roots  (Page-73), Quadratic Congruences  (Page-83), Quadratic Reciprocity (Page-94), Numbers in Other Bases  (Page-106), Duodecimals (Page-114), Decimals (Page-119), Pythagorean Triangles (Page-127), Infinite Descent and Fermat's Conjecture  (Page-135), Sums of Two Squares (Page-143), Sums of Four Squares  (Page-149), Xl - Ny::! = 1 (Page-156),Formulas for Primes (Page-156) Bounds for mx)  (Page-164), Additional Problems (Page-177),  
<br/><br/><label>Dewey Class. No.: </label>512.72,DUD