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A178855 Partial sums of A033485.

%I A178855 #20 Jun 09 2022 02:28:48
%S A178855 1,3,6,11,18,28,41,59,82,112,149,196,253,323,406,507,626,768,933,1128,
%T A178855 1353,1615,1914,2260,2653,3103,3610,4187,4834,5564,6377,7291,8306,
%U A178855 9440,10693,12088,13625,15327,17194,19256,21513,23995,26702,29671,32902,36432
%N A178855 Partial sums of A033485.
%H A178855 Alois P. Heinz, <a href="/A178855/b178855.txt">Table of n, a(n) for n = 1..10000</a>
%F A178855 a(n) = (A033485(2n+1)-1)/2.
%p A178855 b:= proc(n) option remember;
%p A178855       `if`(n<2, n, b(n-1)+b(iquo(n, 2)))
%p A178855     end:
%p A178855 a:= n-> (b(2*n+1)-1)/2:
%p A178855 seq(a(n), n=1..60);  # _Alois P. Heinz_, Feb 17 2022
%o A178855 (Python)
%o A178855 from itertools import islice
%o A178855 from collections import deque
%o A178855 def A178855_gen(): # generator of terms
%o A178855     aqueue, f, b, a = deque([2]), True, 1, 2
%o A178855     while True:
%o A178855         a += b
%o A178855         aqueue.append(a)
%o A178855         if f:
%o A178855             yield (a-1)//2
%o A178855             b = aqueue.popleft()
%o A178855         f = not f
%o A178855 A178885_list = list(islice(A178855_gen(),40)) # _Chai Wah Wu_, Jun 08 2022
%Y A178855 Cf. A000123, A033485.
%K A178855 nonn,easy
%O A178855 1,2
%A A178855 _Philippe Deléham_, Jun 19 2010
%E A178855 a(40) corrected by _Georg Fischer_, Aug 28 2020