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a(n+1) = a(n) + a(floor(n/2)), with a(0)=0, a(1)=1.
4

%I #16 Sep 08 2022 08:45:03

%S 0,1,1,2,3,4,5,7,9,12,15,19,23,28,33,40,47,56,65,77,89,104,119,138,

%T 157,180,203,231,259,292,325,365,405,452,499,555,611,676,741,818,895,

%U 984,1073,1177,1281,1400,1519,1657,1795,1952,2109,2289,2469,2672,2875,3106

%N a(n+1) = a(n) + a(floor(n/2)), with a(0)=0, a(1)=1.

%H Ivan Neretin, <a href="/A062188/b062188.txt">Table of n, a(n) for n = 0..10000</a>

%F G.f. A(x) satisfies: A(x) = x * (1 + (1 + x)*A(x^2))/(1 - x). - _Ilya Gutkovskiy_, May 04 2019

%e a(6) = a(5)+a(2) = 4+1 = 5.

%e a(7) = a(6)+a(3) = 5+2 = 7.

%t Join[{0}, Nest[Append[#, #[[-1]] + #[[Quotient[Length@#, 2]]]] &, {1, 1}, 53]] (* _Ivan Neretin_, Mar 03 2016 *)

%o (Magma) [n le 2 select n-1 else Self(n-1)+Self(Floor(n/2)): n in [1..60]]; // _Vincenzo Librandi_, Mar 03 2016

%o (Python)

%o from itertools import islice

%o from collections import deque

%o def A062188_gen(): # generator of terms

%o aqueue, f, b, a = deque([1]), True, 0, 1

%o yield from (0,1)

%o while True:

%o a += b

%o yield a

%o aqueue.append(a)

%o if f: b = aqueue.popleft()

%o f = not f

%o A062188_list = list(islice(A062188_gen(),40)) # _Chai Wah Wu_, Jun 08 2022

%Y Cf. A033485, A062186, A062187.

%K nonn

%O 0,4

%A _Henry Bottomley_, Jun 13 2001