OFFSET
2,1
FORMULA
a(n) = 2^(-(2*(n-1)-1-floor(log(n-1)/log(2))))*(2*n-1)! for n = 2, 3, 4, ... .
PROG
(PARI) vector(20, n, n++; 2^(-(2*(n-1)-1-floor(log(n-1)/log(2))))*(2*n-1)!) \\ Michel Marcus, Jul 06 2015
(Magma) [2^(-(2*(n-1)-1-Floor(Log(n-1)/Log(2))))*Factorial(2*n-1) : n in [2..30]]; // Vincenzo Librandi, Jul 06 2015
CROSSREFS
A160464 is the Eta triangle.
Equals 2^(-A049039(n-1))*(2*n-1)!
Cf. The pg(n) sequence A162440. - Johannes W. Meijer, Jul 06 2009
KEYWORD
easy,nonn
AUTHOR
Johannes W. Meijer, May 24 2009
STATUS
approved