OFFSET
1,1
COMMENTS
A linear divisibility sequence: Factorizes as a product of second-order and fourth-order linear divisibility sequences. See the Formula section. - Peter Bala, May 02 2014
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..50
FORMULA
From Peter Bala, May 02 2014: (Start)
a(n) = 10*U(n-1,3)*( U(n-1,(7 + sqrt(5))/4)*U(n-1,(7 - sqrt(5))/4) )^2 * ( U(n-1,(9 + sqrt(5))/4)*U(n-1,(9 - sqrt(5))/4) )^2, where U(n,x) is a Chebyshev polynomial of the second kind,
MAPLE
seq(expand(10*ChebyshevU(n-1, 3)*( ChebyshevU(n-1, (7 + sqrt(5))/4)*ChebyshevU(n-1, (7 - sqrt(5))/4) )^2 * ( ChebyshevU(n-1, (9 + sqrt(5))/4)*ChebyshevU(n-1, (9 - sqrt(5))/4) )^2), n = 1..10); # Peter Bala, May 02 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Mar 26 2012
STATUS
approved