login
Number of partitions of 1 into up to n powers of 1/2.
3

%I #14 Nov 09 2017 15:25:15

%S 1,2,3,5,8,13,22,38,66,116,205,364,649,1159,2073,3712,6650,11919,

%T 21370,38322,68732,123287,221158,396744,711760,1276928,2290904,

%U 4110102,7373977,13229810,23735985,42585540,76404334,137080120,245941268,441254018,791673612

%N Number of partitions of 1 into up to n powers of 1/2.

%C 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.

%H Alois P. Heinz, <a href="/A173404/b173404.txt">Table of n, a(n) for n = 1..2000</a>

%F a(n) = Sum_{i=0..n} A002572(i).

%e a(3) = 3: [(1/2)^0], [(1/2)^1,(1/2)^1], [(1/2)^1,(1/2)^2,(1/2)^2].

%Y Partial sums of A002572.

%Y Cf. A002573, A047913, A002574, A049284, A049285, A007178.

%K easy,nonn

%O 1,2

%A _Jonathan Vos Post_, Feb 17 2010