Telephone {Zseq}

Telephone numbers

Description

Under OEIS A000085, a Telephone number - also known as Involution number - is counting the number of connection patterns in a telephone system with n subscribers, or in a more mathematical term, the number of self-inverse permutations on n letters. First 6 Telephone numbers are 1, 1, 2, 4, 10, 26,

Usage

Telephone(n, gmp = TRUE)

Arguments

n

the number of first n entries from the sequence.

gmp

a logical; TRUE to use large number representation, FALSE otherwise.

Value

a vector of length n containing first entries from the sequence.

Examples

## generate first 20 Regular numbers
print(Telephone(20))