|
|
A158421
|
|
a(n) = 1024*n - 1.
|
|
3
|
|
|
1023, 2047, 3071, 4095, 5119, 6143, 7167, 8191, 9215, 10239, 11263, 12287, 13311, 14335, 15359, 16383, 17407, 18431, 19455, 20479, 21503, 22527, 23551, 24575, 25599, 26623, 27647, 28671, 29695, 30719, 31743, 32767, 33791, 34815, 35839
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
The identity (1024*n-1)^2-(1024*n^2-2*n)*(32)^2=1 can be written as a(n)^2-A158420(n)*(32)^2=1.
|
|
LINKS
|
|
|
FORMULA
|
a(n) = 2*a(n-1)-a(n-2).
G.f.: x*(1023+x)/(1-x)^2.
|
|
MATHEMATICA
|
LinearRecurrence[{2, -1}, {1023, 2047}, 50]
|
|
PROG
|
(Magma) I:=[1023, 2047]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]];
(PARI) a(n) = 1024*n - 1.
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|