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A370824 a(n) are the denominators corresponding to A370823(n). 5
1, 5, 19, 13, 211, 95, 2059, 1261, 19171, 5275, 7613, 1159, 1586131, 4766585, 14316139, 505661, 129009091, 2910965, 1161737179, 12675403, 10458256051, 1364211535, 2002867877, 620687383, 847255055011, 2541798719465, 7625463267259, 157769131169, 68629840493971, 86254737475 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
See A370823 for more information.
LINKS
FORMULA
Denominator of 2^(n-1)*(3^n-1)/(3^n-2^n). - Chai Wah Wu, Mar 07 2024
EXAMPLE
A370823(n)/a(n) for n = 1..11: 2/1, 16/5, 104/19, 128/13, 3872/211, 3328/95, 139904/2059, 167936/1261, 5038592/19171, 2748416/5275, 7886848/7613.
MATHEMATICA
Array[Denominator[(3^#-1)/((3/2)^#-1)/2] &, 35] (* Paolo Xausa, Mar 13 2024 *)
PROG
(PARI) \\ See A370823 for functions a370823_4(n)
denominator(a370823_4(n))
(Python)
from math import gcd
def A370824(n): return (a:=3**n-(1<<n))//gcd(a, 3**n-1<<n-1) # Chai Wah Wu, Mar 07 2024
CROSSREFS
A370823 are the corresponding numerators.
Sequence in context: A106229 A129734 A109325 * A169698 A211177 A260645
KEYWORD
nonn,frac
AUTHOR
Hugo Pfoertner, Mar 02 2024
STATUS
approved

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Last modified July 20 18:59 EDT 2024. Contains 374459 sequences. (Running on oeis4.)