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!)
A325254 Number of integer partitions of n with the maximum adjusted frequency depth for partitions of n. 10

%I #15 Sep 13 2023 22:48:02

%S 0,1,1,1,1,3,3,1,3,7,10,17,27,38,1,4,8,17,31,52,83,122,181,257,361,

%T 499,684,910,1211,1595,2060,2663,3406,4315,5426,6784,8417,10466,12824,

%U 15721,19104,23267,1,5,14,36,76,143,269,446,738,1143,1754,2570,3742,5269

%N Number of integer partitions of n with the maximum adjusted frequency depth for partitions of n.

%C The Heinz numbers of these partitions are given by A325283.

%C The adjusted frequency depth of an integer partition is 0 if the partition is empty, and otherwise it is 1 plus the number of times one must take the multiset of multiplicities to reach a singleton. For example, the partition (32211) has adjusted frequency depth 5 because we have: (32211) -> (221) -> (21) -> (11) -> (2). The enumeration of integer partitions by adjusted frequency depth is given by A325280. The adjusted frequency depth of the integer partition with Heinz number n is given by A323014. The maximum adjusted frequency depth for integer partitions of n is given by A325282.

%C Essentially, the last numbers of rows of the array in A225485. - _Clark Kimberling_, Sep 13 2022

%e The a(1) = 1 through a(11) = 17 partitions:

%e 1 11 21 211 221 411 3211 3221 3321 5221 4322

%e 311 3111 4211 4221 5311 4331

%e 2111 21111 32111 4311 6211 4421

%e 5211 32221 5411

%e 32211 33211 6221

%e 42111 42211 6311

%e 321111 43111 7211

%e 52111 33221

%e 421111 42221

%e 3211111 43211

%e 52211

%e 53111

%e 62111

%e 431111

%e 521111

%e 4211111

%e 32111111

%t nn=30;

%t fdadj[ptn_List]:=If[ptn=={},0,Length[NestWhileList[Sort[Length/@Split[#]]&,ptn,Length[#]>1&]]];

%t mfds=Table[Max@@fdadj/@IntegerPartitions[n],{n,nn}];

%t Table[Length[Select[IntegerPartitions[n],fdadj[#]==mfds[[n]]&]],{n,0,nn}]

%Y Cf. A011784, A181819, A182850, A182857, A225486, A323014, A323023, A325246, A325258, A325278, A325281, A325282, A325283.

%Y Integer partition triangles: A008284 (first omega), A116608 (second omega), A325242 (third omega), A325268 (second-to-last omega), A225485 or A325280 (length/frequency depth).

%K nonn

%O 0,6

%A _Gus Wiseman_, Apr 16 2019

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 19 21:09 EDT 2024. Contains 371798 sequences. (Running on oeis4.)