Glasnik Matematicki, Vol. 45, No.2 (2010), 347-355.


Filip Najman

Department of Mathematics, University of Zagreb, Bijenička cesta 30, 10000 Zagreb, Croatia

Abstract.   In this paper, using a method of Luca and the author, we find all values x such that the quadratic forms x2+1, x2+4, x2+2 and x2-2 are 200-smooth and all values x such that the quadratic form x2-4 is 100-smooth.

2000 Mathematics Subject Classification.   11D09, 11Y50.

Key words and phrases.   Pell equation, compact representations, Lucas sequences.

Full text (PDF) (free access)

DOI: 10.3336/gm.45.2.04


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