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a(n) is the denominator of the probability that there is a survivor in "group Russian roulette" starting with n people.
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%I #8 May 04 2024 17:22:34

%S 1,1,4,27,32,28125,2519424,23162146875,458647142400000,

%T 7850009286973311176250,14754517327872000000000000000,

%U 782831631808408787429183093888778240000,14334253326826803757070581682405376000000000000000,6615519361823637433520391368199431823532478208000000000000000

%N a(n) is the denominator of the probability that there is a survivor in "group Russian roulette" starting with n people.

%C See A372480 for more information.

%H Hugo Pfoertner, <a href="/A372487/b372487.txt">Table of n, a(n) for n = 1..41</a>

%e A372487(n)/a(n): 1, 0, 3/4, 16/27, 15/32, 11704/28125, 1105685/2519424, 11327177474/23162146875, 244115733950627/458647142400000, ...

%o (PARI) \\ Uses functions P(n,k) and a372486_7(m) from A372486

%o apply (x->denominator(x), a372486_7(14))

%Y A372486 are the corresponding numerators.

%K nonn,frac

%O 1,3

%A _Hugo Pfoertner_, May 04 2024