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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A343692 a(n) is the number of men's preference profiles in the stable marriage problem with n men and n women, where every man prefers woman number 1 to woman number 2.

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%I A343692 #11 May 26 2021 02:25:39
%S A343692 1,27,20736,777600000,2176782336000000,645362587921121280000000,
%T A343692 27285016590396539545426329600000000,
%U A343692 213106813311662727500673631554480635904000000000,386661002072680852777222237092449665784217600000000000000000000
%N A343692 a(n) is the number of men's preference profiles in the stable marriage problem with n men and n women, where every man prefers woman number 1 to woman number 2.
%C A343692 When implementing the men-proposing Gale-Shapley algorithm on such a preference profile, woman number 1's first engagement comes in an earlier round than the engagement of woman number 2.
%C A343692 This is the same as the number of women's preference profiles in the stable marriage problem with n men and n women, where every woman prefers man number 1 to man number 2.
%H A343692 Wikipedia, <a href="https://en.wikipedia.org/wiki/Gale%E2%80%93Shapley_algorithm">Gale-Shapley algorithm</a>.
%F A343692 a(n) = n!^(n) / 2^n.
%F A343692 a(n) = A338665(n)/n!^(n) = sqrt(A343693(n)).
%e A343692 When n = 2, there is exactly 1 way for each man's profile to be completed such that woman number 1 is before woman number 2. Since we are only looking at men's profiles, this means there are 1^n = 1^2 = 1 preference profiles such that every man prefers woman number 1 to woman number 2.
%t A343692 Table[n!^n/2^n, {n, 2, 10}]
%Y A343692 Cf. A185141, A338665, A343474, A343693.
%K A343692 nonn
%O A343692 2,2
%A A343692 _Tanya Khovanova_ and MIT PRIMES STEP Senior group, May 23 2021