Triangular array

A related concept is that of a triangular matrix.

In mathematics and computing, a triangular array of numbers, polynomials, or the like, is a doubly indexed sequence in which each row is only as long as the row's own index.

The triangular array whose right-hand diagonal sequence consists of Bell numbers

Notable particular examples include these:

• Bell numbers (the "Bell triangle", "Aitken's array", or the "Peirce triangle")
• Bell polynomials
• Boustrophedon transform
• Eulerian number
• Floyd's triangle
• Lozanić's triangle
• Narayana number
• Pascal's triangle
• Rencontres numbers
• Romberg's method
• Stirling numbers of the first kind
• Stirling numbers of the second kind

See also

• Triangular number is the number of entries in such an array.