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A336899
a(n) = denominator(n / (4^n - 2^n)) for n > 0 and a(0) = 1.
1
1, 2, 6, 56, 60, 992, 672, 16256, 8160, 261632, 523776, 4192256, 1397760, 67100672, 134209536, 1073709056, 268431360, 17179738112, 3817734144, 274877382656, 54975528960, 628292059136, 8796090925056, 70368735789056, 11728123330560, 1125899873288192, 2251799780130816
OFFSET
0,2
EXAMPLE
r(n) = 1, 1/2, 1/6, 3/56, 1/60, 5/992, 1/672, 7/16256, 1/8160, 9/261632, ...
MAPLE
r := n -> `if`(n=0, 1, n/(4^n - 2^n)): seq(denom(r(n)), n=0..72);
PROG
(PARI) a(n) = if (n==0, 1, denominator(n / (4^n - 2^n))); \\ Michel Marcus, Aug 28 2020
CROSSREFS
Cf. A336898 (numerator).
Sequence in context: A179389 A084123 A193473 * A181509 A213026 A074023
KEYWORD
nonn,frac
AUTHOR
Peter Luschny, Aug 28 2020
STATUS
approved