The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
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!)
A321142 Number of strict integer partitions of 2*n with no subset summing to n. 30

%I #13 Jan 25 2022 04:20:59

%S 0,1,2,3,5,7,11,15,23,30,43,57,79,102,138,174,232,292,375,471,602,741,

%T 935,1148,1425,1733,2137,2571,3156,3789,4557,5470,6582,7796,9317,

%U 11027,13058,15400,18159,21249,24971,29170,33986,39596,46073,53219,61711,71330,82171

%N Number of strict integer partitions of 2*n with no subset summing to n.

%H Fausto A. C. Cariboni, <a href="/A321142/b321142.txt">Table of n, a(n) for n = 0..200</a>

%e The a(1) = 1 through a(8) = 23 partitions:

%e (2) (4) (6) (8) (10) (12) (14) (16)

%e (3,1) (4,2) (5,3) (6,4) (7,5) (8,6) (9,7)

%e (5,1) (6,2) (7,3) (8,4) (9,5) (10,6)

%e (7,1) (8,2) (9,3) (10,4) (11,5)

%e (5,2,1) (9,1) (10,2) (11,3) (12,4)

%e (6,3,1) (11,1) (12,2) (13,3)

%e (7,2,1) (5,4,3) (13,1) (14,2)

%e (7,3,2) (6,5,3) (15,1)

%e (7,4,1) (8,4,2) (7,5,4)

%e (8,3,1) (8,5,1) (7,6,3)

%e (9,2,1) (9,3,2) (9,4,3)

%e (9,4,1) (9,5,2)

%e (10,3,1) (9,6,1)

%e (11,2,1) (10,4,2)

%e (8,3,2,1) (10,5,1)

%e (11,3,2)

%e (11,4,1)

%e (12,3,1)

%e (13,2,1)

%e (6,5,4,1)

%e (7,4,3,2)

%e (9,4,2,1)

%e (10,3,2,1)

%t Table[Length[Select[IntegerPartitions[n],And[UnsameQ@@#,!Or@@Table[SameQ[Total[#[[s]]],n/2],{s,Subsets[Range[Length[#]]]}]]&]],{n,2,20,2}]

%Y Cf. A002219, A006827, A108917, A237258, A275972, A279791, A284640, A305551.

%K nonn

%O 0,3

%A _Gus Wiseman_, Oct 28 2018

%E a(33)-a(48) from _Giovanni Resta_, Oct 30 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 May 23 12:41 EDT 2024. Contains 372763 sequences. (Running on oeis4.)