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A325690 Number of length-3 integer partitions of n whose largest part is not the sum of the other two. 8

%I #14 Feb 19 2022 20:28:03

%S 0,0,0,1,0,2,2,4,3,7,6,10,9,14,13,19,17,24,23,30,28,37,35,44,42,52,50,

%T 61,58,70,68,80,77,91,88,102,99,114,111,127,123,140,137,154,150,169,

%U 165,184,180,200,196,217,212,234,230,252,247,271,266,290,285,310

%N Number of length-3 integer partitions of n whose largest part is not the sum of the other two.

%C Confirmed recurrence relation from _Colin Barker_ for n <= 10000. - _Fausto A. C. Cariboni_, Feb 19 2022

%H Fausto A. C. Cariboni, <a href="/A325690/b325690.txt">Table of n, a(n) for n = 0..10000</a>

%F Conjectures from _Colin Barker_, May 15 2019: (Start)

%F G.f.: x^3*(1 + x^2 + x^3 + x^4) / ((1 - x)^3*(1 + x)^2*(1 + x^2)*(1 + x + x^2)).

%F a(n) = a(n-2) + a(n-3) + a(n-4) - a(n-5) - a(n-6) - a(n-7) + a(n-9) for n>8.

%F (End)

%e The a(3) = 1 through a(13) = 14 partitions (A = 10, B = 11):

%e (111) (221) (222) (322) (332) (333) (433) (443) (444) (544)

%e (311) (411) (331) (521) (432) (442) (533) (543) (553)

%e (421) (611) (441) (622) (542) (552) (643)

%e (511) (522) (631) (551) (732) (652)

%e (531) (721) (632) (741) (661)

%e (621) (811) (641) (822) (733)

%e (711) (722) (831) (742)

%e (731) (921) (751)

%e (821) (A11) (832)

%e (911) (841)

%e (922)

%e (931)

%e (A21)

%e (B11)

%t Table[Length[Select[IntegerPartitions[n,{3}],#[[1]]!=#[[2]]+#[[3]]&]],{n,0,30}]

%Y Column k = 3 of A325592.

%Y Cf. A000041, A001399, A005044, A008642, A069905, A266223.

%Y Cf. A325689, A325691, A325694.

%K nonn

%O 0,6

%A _Gus Wiseman_, May 15 2019

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Last modified March 28 10:55 EDT 2024. Contains 371241 sequences. (Running on oeis4.)