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!)
A241131 Number of partitions p of n such that (maximal multiplicity over the parts of p) = number of 1s in p. 22

%I #18 Mar 16 2024 13:27:29

%S 0,1,1,2,3,4,7,9,13,18,26,32,47,60,79,104,137,173,227,285,365,461,583,

%T 724,912,1129,1403,1729,2137,2611,3211,3906,4765,5777,7010,8450,10213,

%U 12263,14738,17637,21113,25158,30008,35638,42333,50130,59346,70035,82663

%N Number of partitions p of n such that (maximal multiplicity over the parts of p) = number of 1s in p.

%H Alois P. Heinz, <a href="/A241131/b241131.txt">Table of n, a(n) for n = 0..2000</a> (first 301 terms from John Tyler Rascoe)

%F G.f.: Sum_{i>0} x^i * Product_{j>1} ((1 - x^(j*(i+1)))/(1 - x^j)). - _John Tyler Rascoe_, Mar 12 2024

%e a(6) counts these 7 partitions: 51, 411, 321, 3111, 2211, 21111, 111111.

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

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

%p end:

%p a:= n-> `if`(n=0, 0, b(n$2, 0)):

%p seq(a(n), n=0..48); # _Alois P. Heinz_, Mar 15 2024

%t z = 30; m[p_] := Max[Map[Length, Split[p]]]; Table[Count[IntegerPartitions[n], p_ /; m[p] == Count[p, 1]], {n, 0, z}]

%o (PARI)

%o A_x(N)={my(x='x+O('x^N),g=sum(i=1, N, x^i*prod(j=2, N, (1-x^(j*(i+1)))/(1-x^j))));

%o concat([0],Vec(g))}

%o A_x(50) \\ _John Tyler Rascoe_, Mar 12 2024

%Y Cf. A241090, A241132.

%K nonn,easy

%O 0,4

%A _Clark Kimberling_, Apr 24 2014

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 20:33 EDT 2024. Contains 371916 sequences. (Running on oeis4.)