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A248592 Denominators of the (simplified) rational numbers n*2^(n - 1)/(n - 1)! . 4

%I

%S 1,1,1,3,3,5,45,315,35,567,14175,51975,467775,868725,2837835,

%T 638512875,638512875,1206079875,97692469875,371231385525,441942125625,

%U 17717861581875,2143861251406875,16436269594119375,5917057053882975,284473896821296875,1780595872696265625

%N Denominators of the (simplified) rational numbers n*2^(n - 1)/(n - 1)! .

%H James Burling, <a href="/A248591/a248591_2.pdf">Another Special Rational Sequence</a>

%F a(n) = denom(n * 2^(n - 1) / (n - 1)!).

%F a(n) = denom(g(1, n)) where g(m, n) = m if m = n; 2g(m + 1, n)/m otherwise.

%p A248592 := proc(n)

%p n*2^(n-1)/(n-1)! ;

%p denom(%) ;

%p end proc:

%p seq(A248592(n),n=1..30) ; # _R. J. Mathar_, Oct 10 2014

%o (PARI) vector(40, n, denominator(n*2^(n - 1)/(n - 1)!)) \\ _Michel Marcus_, Oct 09 2014

%Y Cf. A248591 (numerators).

%Y Has same start as A241591 but is a different sequence.

%K frac,nonn

%O 1,4

%A _James Burling_, Oct 09 2014

%E More terms from _Michel Marcus_, Oct 09 2014

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Last modified January 29 04:46 EST 2020. Contains 331335 sequences. (Running on oeis4.)