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Numbers that occur exactly 3 times in A036038, i.e., numbers m such that the multinomial coefficient (x_1 + ... + x_k)!/(x_1! * ... * x_k!) is equal to m for exactly 3 integer partitions (x_1, ..., x_k).
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%I #7 Sep 23 2024 11:33:28

%S 6,20,30,56,60,90,105,252,360,462,495,504,560,720,756,990,1320,1365,

%T 1540,1716,2970,3360,3960,4290,4620,5460,6006,6435,7920,8190,10080,

%U 10296,10626,10920,11628,12012,12870,14280,15504,17550,18360,21840,23256,24024,24310

%N Numbers that occur exactly 3 times in A036038, i.e., numbers m such that the multinomial coefficient (x_1 + ... + x_k)!/(x_1! * ... * x_k!) is equal to m for exactly 3 integer partitions (x_1, ..., x_k).

%C Numbers m such that A376369(m) = 3, i.e., numbers that appear exactly 3 times in A376367.

%H Pontus von Brömssen, <a href="/A376373/b376373.txt">Table of n, a(n) for n = 1..10000</a>

%e 6 is a term, because it can be represented as a multinomial coefficient in exactly 3 ways: 6 = 6!/(1!*5!) = 4!/(2!*2!) = 3!/(1!*1!*1!).

%Y Third row of A376370.

%Y Subsequence of A325593.

%Y Cf. A036038, A376367, A376369.

%K nonn

%O 1,1

%A _Pontus von Brömssen_, Sep 23 2024