OFFSET
1,1
COMMENTS
A linear divisibility sequence. Factorizes as a product of second-order and fourth-order linear divisibility sequences. See Formula section. - Peter Bala, May 02 2014
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..50
FORMULA
a(n) = 8*U(n-1,2)^2*U(n-1,3)*( U(n-1,(4+sqrt(2))/2)*U(n-1,(4-sqrt(2))/2) )^2 = 8*A001353(n)^2 * A001109(n) * A161158(n-1)^2, where U(n,x) is a Chebyshev polynomial of the second kind. - Peter Bala, May 02 2014
MAPLE
seq(expand(8*ChebyshevU(n-1, 2)^2*ChebyshevU(n-1, 3)*( ChebyshevU(n-1, (4+sqrt(2))/2)*ChebyshevU(n-1, (4-sqrt(2))/2) )^2), n = 1..10); # Peter Bala, May 02 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Mar 26 2012
STATUS
approved