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%I #17 Dec 23 2024 14:53:44
%S 0,1,5,9,15,30,40,51,76,90,106,123,141,180,201,223,246,270,295,321,
%T 348,376,405,436,468,501,535,606,643,681,720,761,803,846,890,935,1028,
%U 1076,1125,1175,1227,1280,1334,1389,1445,1502,1619,1679,1740,1802,1865,1929,1994,2060,2127,2195,2264
%N Numbers missing in A249299 = list {b(n)} of numbers such that Sum_{k=1..b(n)} b(k) is not in the list.
%H M. F. Hasler, <a href="/A249331/b249331.txt">Table of n, a(n) for n = 1..931</a>
%H E. Angelini, <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2014-October/013862.html">Sum of the a(n) first terms of S is not in S</a>, SeqFan list, Oct 2014
%o (PARI) A249299=[]; A249331=[s=0, 1]; for(n=2, 999, setsearch(A249331, n)&&next;A249299=concat(A249299, n); s+=n; setsearch(A249299, #A249299)&&A249331=concat(A249331, s))
%K nonn
%O 1,3
%A _Eric Angelini_ and _M. F. Hasler_, Oct 24 2014