|
|
A049897
|
|
a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = 2^(p+1) + 2 - n and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 and a(3) = 4.
|
|
0
|
|
|
1, 1, 4, 5, 10, 16, 33, 69, 138, 208, 452, 921, 1848, 3701, 7403, 14809, 29618, 44428, 96262, 196226, 394305, 789537, 1579543, 3159330, 6318730, 12637529, 25275094, 50550205, 101100416, 202200837, 404401675, 808803353, 1617606706
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,3
|
|
LINKS
|
|
|
MAPLE
|
s := proc(n) option remember; `if`(n < 1, 0, a(n) + s(n - 1)) end proc:
a := proc(n) option remember;
`if`(n < 4, [1, 1, 4][n], s(n - 1) - a(2^ceil(log[2](n - 1)) + 2 - n)):
end proc:
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|