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Numbers that occur exactly once in A036038, i.e., numbers m such that the multinomial coefficient (x_1 + ... + x_k)!/(x_1! * ... * x_k!), with 1 <= x_1 <= ... <= x_k, is equal to m only when (x_1, ..., x_k) = (1, m-1).
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%I #6 Sep 23 2024 11:32:44

%S 2,3,4,5,7,8,9,11,13,14,16,17,18,19,22,23,25,26,27,29,31,32,33,34,37,

%T 38,39,40,41,43,44,46,47,48,49,50,51,52,53,54,57,58,59,61,62,63,64,65,

%U 67,68,69,71,73,74,75,76,77,79,80,81,82,83,85,86,87,88,89

%N Numbers that occur exactly once in A036038, i.e., numbers m such that the multinomial coefficient (x_1 + ... + x_k)!/(x_1! * ... * x_k!), with 1 <= x_1 <= ... <= x_k, is equal to m only when (x_1, ..., x_k) = (1, m-1).

%C Numbers m such that A376369(m) = 1, i.e., numbers that appear only once in A376367.

%H Pontus von Brömssen, <a href="/A376371/b376371.txt">Table of n, a(n) for n = 1..10000</a>

%e 10 is not a term, because it can be represented as a multinomial coefficient in 2 ways: 10 = 10!/(1!*9!) = 5!/(2!*3!).

%Y First row of A376370.

%Y Complement of A325472 (with respect to the positive integers).

%Y Cf. A036038, A376367, A376369.

%K nonn

%O 1,1

%A _Pontus von Brömssen_, Sep 23 2024