# Lagrange’s Four-Square Theorem

Formalized Mathematics (2014)

- Volume: 22, Issue: 2, page 105-110
- ISSN: 1426-2630

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topYasushige Watase. "Lagrange’s Four-Square Theorem." Formalized Mathematics 22.2 (2014): 105-110. <http://eudml.org/doc/268883>.

@article{YasushigeWatase2014,

abstract = {This article provides a formalized proof of the so-called “the four-square theorem”, namely any natural number can be expressed by a sum of four squares, which was proved by Lagrange in 1770. An informal proof of the theorem can be found in the number theory literature, e.g. in [14], [1] or [23]. This theorem is item #19 from the “Formalizing 100 Theorems” list maintained by Freek Wiedijk at http://www.cs.ru.nl/F.Wiedijk/100/.},

author = {Yasushige Watase},

journal = {Formalized Mathematics},

keywords = {Lagrange’s four-square theorem},

language = {eng},

number = {2},

pages = {105-110},

title = {Lagrange’s Four-Square Theorem},

url = {http://eudml.org/doc/268883},

volume = {22},

year = {2014},

}

TY - JOUR

AU - Yasushige Watase

TI - Lagrange’s Four-Square Theorem

JO - Formalized Mathematics

PY - 2014

VL - 22

IS - 2

SP - 105

EP - 110

AB - This article provides a formalized proof of the so-called “the four-square theorem”, namely any natural number can be expressed by a sum of four squares, which was proved by Lagrange in 1770. An informal proof of the theorem can be found in the number theory literature, e.g. in [14], [1] or [23]. This theorem is item #19 from the “Formalizing 100 Theorems” list maintained by Freek Wiedijk at http://www.cs.ru.nl/F.Wiedijk/100/.

LA - eng

KW - Lagrange’s four-square theorem

UR - http://eudml.org/doc/268883

ER -

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