Note sur le nombre des marches rentrantes, que l'on peut obtenir en remplissant successivement les deux demi-échiquiers rectangulaires ayant pour frontière commune l'une des médianes de l'échiquier total
MSC 2010: 11B83, 05A19, 33C45This paper is dealing with the Hankel determinants of the special number sequences given in an integral form. We show that these sequences satisfy a generalized convolution property and the Hankel determinants have the generalized Somos-4 property. Here, we recognize well known number sequences such as: the Fibonacci, Catalan, Motzkin and SchrÄoder sequences, like special cases.