OFFSET
1,1
COMMENTS
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
FORMULA
a(n) = (9-(-1)^n)*2^(1/4*(2*n-5+(-1)^n)).
G.f.: x*(5+8*x)/(1-2*x^2).
PROG
(MAGMA) [ n le 2 select 2+3*n else 2*Self(n-2): n in [1..40] ];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Aug 21 2009
STATUS
proposed