login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A286075 Number of permutations of [n] with increasing cycle sizes. 8

%I #7 May 28 2018 09:19:56

%S 1,1,1,3,8,38,182,1194,7932,69192,591936,6286272,66914880,840036960,

%T 10567285920,154755036000,2246755924800,37283584936320,

%U 618705247829760,11472473012232960,212762383625594880,4386435706887413760,89954629722500659200,2030764767987849062400

%N Number of permutations of [n] with increasing cycle sizes.

%C Each cycle is written with the smallest element first and cycles are arranged in increasing order of their first elements.

%H Alois P. Heinz, <a href="/A286075/b286075.txt">Table of n, a(n) for n = 0..450</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Permutation">Permutation</a>

%p b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i>n, 0,

%p b(n, i+1)+b(n-i, i+1)*(i-1)!*binomial(n-1, i-1)))

%p end:

%p a:= n-> b(n, 1):

%p seq(a(n), n=0..30);

%t b[n_, i_] := b[n, i] = If[n == 0, 1, If[i > n, 0, b[n, i + 1] + b[n - i, i + 1]*(i - 1)!*Binomial[n - 1, i - 1]]];

%t a[n_] := b[n, 1];

%t Table[a[n], {n, 0, 30}] (* _Jean-François Alcover_, May 28 2018, from Maple *)

%Y Cf. A275312, A286071, A286072, A286073, A286074, A286076, A286077.

%K nonn

%O 0,4

%A _Alois P. Heinz_, May 01 2017

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 25 20:05 EDT 2024. Contains 374612 sequences. (Running on oeis4.)