In mathematics, the Genocchi numbers Gn, named after Angelo Genocchi, are a sequence of integers that satisfy the relation
The first few Genocchi numbers are 1, −1, 0, 1, 0, −3, 0, 17 (sequence in the OEIS), see .
There are two cases for .
is an autosequence (a sequence whose inverse binomial transform is the signed sequence) of the first kind (its main diagonal is 0's = ). An autosequence of the second kind has its main diagonal equal to the first upper diagonal multiplied by 2. Example: / .