# Tribonacci number

From Encyclopedia of Mathematics

A member of the Tribonacci sequence. The formula for the th number is given by A. Shannon in [a1]:

Binet's formula for the th number is given by W. Spickerman in [a2]:

where

and is the complex conjugate of .

#### References

[a1] | A. Shannon, "Tribonacci numbers and Pascal's pyramid" The Fibonacci Quart. , 15 : 3 (1977) pp. 268; 275 |

[a2] | W. Spickerman, "Binet's formula for the Tribonacci sequence" The Fibonacci Quart. , 15 : 3 (1977) pp. 268; 275 |

**How to Cite This Entry:**

Tribonacci number.

*Encyclopedia of Mathematics.*URL: http://www.encyclopediaofmath.org/index.php?title=Tribonacci_number&oldid=17204

This article was adapted from an original article by Krassimir Atanassov (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article