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A048205 a(n)=T(n+2,n), array T given by A048201.

%I A048205 #12 Sep 02 2025 15:47:52
%S A048205 4,9,17,27,41,56,72,93,115,140,166,194,227,261,296,332,370,410,452,
%T A048205 498,546,595,645,698,755,815,877,941,1006,1076,1153,1233,1314,1397,
%U A048205 1482,1568,1658,1749,1841,1941,2045,2152,2260,2376
%N A048205 a(n)=T(n+2,n), array T given by A048201.
%H A048205 Chai Wah Wu, <a href="/A048205/b048205.txt">Table of n, a(n) for n = 1..10000</a>
%F A048205 a(n) = A004978(n+3) - 4. - _Sean A. Irvine_, Jun 05 2021
%o A048205 (Python)
%o A048205 from itertools import count, accumulate, islice
%o A048205 from collections import deque
%o A048205 def A048205_gen(): # generator of terms
%o A048205     aset, alist, c = {1,3}, deque([2,1]), 0
%o A048205     for k in count(3):
%o A048205         if k in aset:
%o A048205             aset.remove(k)
%o A048205         else:
%o A048205             yield (c:=c+k)
%o A048205             aset |= set(k+d for d in accumulate(alist))
%o A048205             alist.appendleft(k)
%o A048205 A048205_list = list(islice(A048205_gen(),50)) # _Chai Wah Wu_, Sep 02 2025
%Y A048205 Cf. A004978.
%K A048205 nonn,changed
%O A048205 1,1
%A A048205 _Clark Kimberling_