|
|
A173404
|
|
Number of partitions of 1 into up to n powers of 1/2.
|
|
3
|
|
|
1, 2, 3, 5, 8, 13, 22, 38, 66, 116, 205, 364, 649, 1159, 2073, 3712, 6650, 11919, 21370, 38322, 68732, 123287, 221158, 396744, 711760, 1276928, 2290904, 4110102, 7373977, 13229810, 23735985, 42585540, 76404334, 137080120, 245941268, 441254018, 791673612
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
Partial sums of number of partitions of 1 into n powers of 1/2. Partial sums of (according to one definition of "binary") the number of binary rooted trees. The subsequence of primes in this partial sum begins: 2, 3, 5, 13, a(43) = 26405436301.
|
|
LINKS
|
|
|
FORMULA
|
|
|
EXAMPLE
|
a(3) = 3: [(1/2)^0], [(1/2)^1,(1/2)^1], [(1/2)^1,(1/2)^2,(1/2)^2].
|
|
CROSSREFS
|
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|