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A303449
Denominator of (2*n+1)/(2^(2*n+1)-1).
1
1, 7, 31, 127, 511, 2047, 8191, 32767, 131071, 524287, 299593, 8388607, 33554431, 134217727, 536870911, 2147483647, 8589934591, 34359738367, 137438953471, 549755813887, 2199023255551, 8796093022207, 35184372088831, 140737488355327, 562949953421311, 2251799813685247
OFFSET
0,2
COMMENTS
If A160145(n) = 0, then a(n) = A083420(n).
Least values of k such that a(k) = A083420(k)/A036259(n) are 0, 10, 126, 77, 540, 73, 1242, 328, 1540, 489 for 1 <= n <= 10.
MAPLE
seq(denom((2*n+1)/(2^(2*n+1)-1)), n=0..25);
PROG
(PARI) a(n) = denominator((2*n+1)/(2^(2*n+1)-1));
(PARI) forstep(k=1, 1e2, 2, print1(denominator(k/(2^k-1)), ", "));
CROSSREFS
Cf. A005408, A036259, A083420, A160144 (numerators), A160145.
Sequence in context: A002147 A169785 A255282 * A083420 A277002 A282898
KEYWORD
nonn,easy,frac
AUTHOR
Altug Alkan, Apr 24 2018
STATUS
approved