

A203427


a(n) = w(n+1)/(4*w(n)), where w = A203426.


3



3, 48, 1000, 25920, 806736, 29360128, 1224440064, 57600000000, 3018173044480, 174359297654784, 11011033460963328, 754709361539940352, 55801305000000000000
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


LINKS

Table of n, a(n) for n=1..13.


FORMULA

a(n) = (1/4) * (n+1) * (2(n+2))^n.  Andrei Asinowski, Nov 03 2015


MATHEMATICA

f[j_] := 1/(2 j + 2); z = 12;
v[n_] := Product[Product[f[k]  f[j], {j, 1, k  1}], {k, 2, n}];
1/Table[v[n], {n, 1, z}] (* A203426 *)
Table[v[n]/(4 v[n + 1]), {n, 1, z  1}] (* A203427 *)


CROSSREFS

Cf. A203426, A203425.
Sequence in context: A270005 A218382 A195635 * A320668 A319732 A199012
Adjacent sequences: A203424 A203425 A203426 * A203428 A203429 A203430


KEYWORD

sign


AUTHOR

Clark Kimberling, Jan 02 2012


EXTENSIONS

Name corrected by Andrei Asinowski, Nov 03 2015


STATUS

approved



