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A370826 a(n) are the denominators corresponding to A370825(n).

%I A370826 #13 Mar 11 2024 11:59:39
%S A370826 2,1,14,1,62,3,254,17,1022,31,178,3,16382,5461,65534,257,262142,657,
%T A370826 1048574,1271,4194302,60787,356962,12291,67108862,22369621,268435454,
%U A370826 617093,1073741822,149943,4294967294,16843009,746950834,5726623061,967879954,981,274877906942
%N A370826 a(n) are the denominators corresponding to A370825(n).
%C A370826 See A370825 for more information.
%H A370826 Paolo Xausa, <a href="/A370826/b370826.txt">Table of n, a(n) for n = 1..2000</a>
%F A370826 A370825(n)/a(n) = (3/4) * (3^n - 1) / (2^n - 1).
%e A370826 A370825(n)/a(n) for n=1..14: 3/2, 2, 39/14, 4, 363/62, 26/3, 3279/254, 328/17, 29523/1022, 1342/31, 11553/178, 292/3, 2391483/16382, 1195742/5461.
%t A370826 Array[Denominator[3/4*(3^#-1)/(2^#-1)] &, 50] (* _Paolo Xausa_, Mar 11 2024 *)
%o A370826 (PARI) a370826(n) = denominator((3/4) * (3^n - 1) / (2^n - 1));
%o A370826 (Python)
%o A370826 from math import gcd
%o A370826 def A370826(n): return (a:=(1<<n+1)-2)//gcd(a,3**(n+1)-3>>1) # _Chai Wah Wu_, Mar 10 2024
%Y A370826 A370825 are the corresponding numerators.
%Y A370826 Cf. A370823, A370824.
%K A370826 nonn,frac,easy
%O A370826 1,1
%A A370826 _Hugo Pfoertner_, Mar 08 2024