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!)
A320736 Number of partitions of n with five sorts of part 1 which are introduced in ascending order. 4

%I #8 Dec 07 2020 08:24:35

%S 1,1,3,7,20,63,232,944,4158,19236,91794,446311,2194569,10863768,

%T 53995350,269013587,1342192961,6702368648,33486112079,167353481065,

%U 836536395240,4181989400979,20907870188551,104533122311131,522646929294281,2613178606952285

%N Number of partitions of n with five sorts of part 1 which are introduced in ascending order.

%H Alois P. Heinz, <a href="/A320736/b320736.txt">Table of n, a(n) for n = 0..1433</a>

%p b:= proc(n, i) option remember; `if`(n=0 or i<2, add(

%p Stirling2(n, j), j=0..5), add(b(n-i*j, i-1), j=0..n/i))

%p end:

%p a:= n-> b(n$2):

%p seq(a(n), n=0..40);

%t b[n_, i_] := b[n, i] = If[n == 0 || i < 2, Sum[StirlingS2[n, j], {j, 0, 5}], Sum[b[n - i j, i - 1], {j, 0, n/i}]];

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

%t a /@ Range[0, 40] (* _Jean-François Alcover_, Dec 07 2020, after _Alois P. Heinz_ *)

%Y Column k=5 of A292745.

%K nonn

%O 0,3

%A _Alois P. Heinz_, Oct 20 2018

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 April 23 07:34 EDT 2024. Contains 371905 sequences. (Running on oeis4.)