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A048204 a(n) = T(n+1,n), array T given by A048201.

%I A048204 #17 Sep 02 2025 09:22:34
%S A048204 2,6,11,19,29,43,58,74,95,117,142,168,196,229,263,298,334,372,412,454,
%T A048204 500,548,597,647,700,757,817,879,943,1008,1078,1155,1235,1316,1399,
%U A048204 1484,1570,1660,1751,1843,1943,2047,2154,2262,2378,2497,2621,2748,2880,3013
%N A048204 a(n) = T(n+1,n), array T given by A048201.
%H A048204 Chai Wah Wu, <a href="/A048204/b048204.txt">Table of n, a(n) for n = 1..10000</a>
%F A048204 a(n) = A004978(n+2) - 2. - _Sean A. Irvine_, Jun 05 2021
%o A048204 (Python)
%o A048204 from itertools import count, accumulate, islice
%o A048204 from collections import deque
%o A048204 def A048204_gen(): # generator of terms
%o A048204     aset, alist, c = {1}, deque([1]), 0
%o A048204     for k in count(2):
%o A048204         if k in aset:
%o A048204             aset.remove(k)
%o A048204         else:
%o A048204             yield (c:=c+k)
%o A048204             aset |= set(k+d for d in accumulate(alist))
%o A048204             alist.appendleft(k)
%o A048204 A048204_list = list(islice(A048204_gen(),50)) # _Chai Wah Wu_, Sep 01 2025
%Y A048204 Cf. A004978, A048201.
%K A048204 nonn,changed
%O A048204 1,1
%A A048204 _Clark Kimberling_