Si tenim prou energia i pacičncia és possible resoldre el problema dels ponts de Köningsberg. Només cal que remuntem el riu fins el naixement. D'aquesta manera "convertim" les dues ribes en una de sola i la paritat i senaritat de cada zona de terra varia fent possible la passejada.

Amb la manera d'abordar el problema dels ponts de Köningsberg Euler va inaugurar una nova i important branca de la matemŕtica coneguda com a Teoria de Grafs. Per "commemorar-ho" Bohdan Zelinka (text) i Zdenek Ryjacek (música) van crear aquest "Himne a la Teoria de Grafs" que donem aquí en la seva versió anglesa deguda a Donald A. Preece.

En aquesta adreça podreu accedir a un arxiu d'ŕudio (en txec) i a un vídeo (sense so) en el que es veu als esforçats intčrprets.

http://www.iif.hu/~visontay/ponticulus/britannicus/humor/graph-hymn-mm.html

  1.
Seven bridges spanned the River Pregel, 
Many more than might have been expected; 
Königsberg's wise leaders were delighted 
To have built such very splendid structures.

    2.
Crowds each ev'ning surged towards the river, 
People walked bemused across the bridges, 
Pondering a simple-sounding challenge 
Which defeated them and left them puzzled.

    3.
Here's the problem; see if you can solve it! 
Try it out at home an scraps of paper! 
STARTING OUT AND ENDING AT THE SAME SPOT, 
YOU MUST CROSS EACH BRIDGE JUST ONCE EACH EV'NING.

    Refrain:
Eulerian graphs all have this restriction: 
THE DEGREE OF ANY POINT IS EVEN. 
That's the oldest graph result 
That mankind has ever known.

   4.
All the folk in Königsberg were frantic! 
All their efforts ended up in failure! 
Happily, a learn-ed math'matician 
Had his house right there within the city.

    5.
Euler's mind was equal to the problem: 
"Ah", he said, "You're bound to be disheartened. 
Crossing each bridge only once per outing 
Can't be done, I truly do assure you."

    Refrain:
Eulerian graphs …

    6.
Laws of Nature never can be altered, 
We can'd change them, even if we wish to. 
Nor can flooded rivers or great bridges 
Interfere with scientific progress.

    7.
War brought strife and ruin to the Pregel; 
Bombs destroyed those seven splendid bridges. 
Euler's name and fame will, notwithstanding, 
Be recalled with Königsberg's for ever.

    Refrain:
Eulerian graphs …

    8.
Thanks to Euler, Graph Theory is thriving. 
Year by year it flourishes and blossoms, 
Fertilising much of mathematics 
And so rich in all its applications.

    9.
Colleagues, let us fill up all our glasses! 
Colleagues, let us raise them now to toast the 
Greatness and the everlasting glory 
Of our Graph Teohry, which we love dearly!