Telephone

A000085

Involution

Under OEIS <a href="https://oeis.org/A000085">A000085</a>, a Telephone number - also known as Involution number - is counting the number
of connection patterns in a telephone system with <code>n</code> subscribers, or in a more mathematical term, the number of self-inverse permutations on
<code>n</code> letters. First 6 Telephone numbers are 	1, 1, 2, 4, 10, 26,

Generates well-known integer sequences. 'gmp' package is adopted for computing with arbitrarily large numbers. Every function has hyperlink to its corresponding item in OEIS (The On-Line Encyclopedia of Integer Sequences) in the function help page. For interested readers, see Sloane and Plouffe (1995, ISBN:978-0125586306).

Kisung You

Zseq

Integer Sequence Generator

Telephone function

<dl><dt>n</dt>
<dd>the number of first <code>n</code> entries from the sequence.</dd>
<dt>gmp</dt>
<dd>a logical; <code>TRUE</code> to use large number representation, <code>FALSE</code> otherwise.</dd></dl>

Arguments

Under OEIS <a href='https://oeis.org/A000085'>A000085</a>, a Telephone number - also known as Involution number - is counting the number
of connection patterns in a telephone system with <code>n</code> subscribers, or in a more mathematical term, the number of self-inverse permutations on
<code>n</code> letters. First 6 Telephone numbers are 	1, 1, 2, 4, 10, 26,

Telephone numbers — Telephone

<dl>

<dt>n</dt>
<dd>the number of first <code>n</code> entries from the sequence.</dd>


<dt>gmp</dt>
<dd>a logical; <code>TRUE</code> to use large number representation, <code>FALSE</code> otherwise.</dd>

</dl>

Telephone: Telephone numbers

Description

Usage

Value

Arguments

Examples