

A081265


Triangle of coefficients of solutions to a(n)=2*a(n1)+k^2*a(n2), a(0)=1, a(1)=1.


2



1, 1, 0, 2, 0, 1, 4, 0, 3, 0, 8, 0, 8, 0, 1, 16, 0, 20, 0, 5, 0, 32, 0, 48, 0, 18, 0, 1, 64, 0, 112, 0, 56, 0, 7, 0, 128, 0, 256, 0, 160, 0, 32, 0, 1, 256, 0, 576, 0, 432, 0, 120, 0, 9, 0, 512, 0, 1280, 0, 1120, 0, 400, 0, 50, 0, 1, 1024, 0, 2816, 0, 2816, 0, 1232, 0, 220
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,4


COMMENTS

Unsigned Chebyshev numbers of the first kind. Columns include A011782, A001792, A001793, A001794, A006974.


LINKS

Table of n, a(n) for n=0..74.


FORMULA

Triangle is generated by T(n, k)=((1+sqrt(k^2+1))^n+(1sqrt(k^2+1))^n)/2.


EXAMPLE

Triangle rows are {1}, {1,0}, {2,0,1}, {4,0,3,0}, {8,0,8,0,1},.... [Corrected by Philippe Deléham, Dec 27 2007]


CROSSREFS

Cf. A008310.
Sequence in context: A230747 A181670 A039991 * A108643 A133838 A182138
Adjacent sequences: A081262 A081263 A081264 * A081266 A081267 A081268


KEYWORD

easy,nonn,tabl


AUTHOR

Paul Barry, Mar 15 2003


STATUS

approved



