A248591 Numerators of the (simplified) rationals n*2^(n - 1)/(n - 1)! .

1, 4, 6, 16, 10, 8, 28, 64, 2, 8, 44, 32, 52, 16, 8, 256, 34, 8, 76, 32, 4, 16, 184, 128, 4, 16, 8, 64, 232, 32, 496, 1024, 2, 8, 4, 32, 148, 16, 8, 128, 164, 16, 344, 64, 8, 32, 752, 512, 4, 16, 8, 64, 424, 32, 16, 256, 8, 32, 944, 128, 976, 64, 32, 4096, 2

Offset: 1

Author

James Burling, Oct 09 2014

Keywords

• frac
• nonn

Links

• James Burling, Another Special Rational Sequence

Crossrefs

Cf. A248592 (denominators).

Programs

Magma

[Numerator(n*2^(n-1)/Factorial(n-1)): n in [1..70]]; // Vincenzo Librandi, Oct 16 2014

Mathematica

Table[Numerator[n 2^(n - 1)/(n - 1)!], {n, 1, 70}] (* Vincenzo Librandi, Oct 16 2014 *)

PARI

vector(100, n, numerator(n*2^(n - 1)/(n - 1)!)) \\ Michel Marcus, Oct 09 2014

Formula

a(n) = numerator(n*2^(n - 1)/(n - 1)!).

a(n) = numerator(g(1, n)) where g(m, n) = m if m = n; 2*g(m + 1, n)/m otherwise.

Extensions

More terms from Michel Marcus, Oct 09 2014