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A007962 a(n) is the largest odd number k such that 9, 11, ..., k are sums of 3 of first n odd primes.

%I A007962 #21 Jul 10 2021 19:31:52
%S A007962 9,15,21,29,39,47,57,65,71,93,99,115,129,137,143,149,183,189,205,219,
%T A007962 225,241,251,269,287,309,317,327,335,357,371,377,417,419,441,459,465,
%U A007962 493,503,509,543,545,567,587,597,609,621,653,657,695,701,723,725,743,749,755,785
%N A007962 a(n) is the largest odd number k such that 9, 11, ..., k are sums of 3 of first n odd primes.
%C A007962 From _Rémy Sigrist_, Aug 20 2017: (Start)
%C A007962 The following table gives the first index (n0) of the term that starts the first run of j consecutive equal terms for j=1..6:
%C A007962 j   n0     a(n0)
%C A007962 -   ----   ------
%C A007962 1      1        9
%C A007962 2     96     1511
%C A007962 3    131     2205
%C A007962 4    334     6733
%C A007962 5   5959   176843
%C A007962 6   3079    84731
%C A007962 (End)
%H A007962 Rémy Sigrist, <a href="/A007962/b007962.txt">Table of n, a(n) for n = 1..10000</a>
%H A007962 K. Kashihara, <a href="http://www.gallup.unm.edu/~smarandache/Kashihara.pdf">Comments and Topics on Smarandache Notions and Problems</a>, Erhus University Press, 1996, 50 pages. See page 20.
%H A007962 K. Kashihara, <a href="/A011772/a011772.pdf">Comments and Topics on Smarandache Notions and Problems</a>, Erhus University Press, 1996, 50 pages. [Cached copy] See page 20.
%H A007962 F. Smarandache, <a href="http://www.gallup.unm.edu/~smarandache/OPNS.pdf">Only Problems, Not Solutions!</a>
%H A007962 Rémy Sigrist, <a href="/A007962/a007962.gp.txt">PARI program for A007962</a>
%F A007962 a(n) << n log n. - _Charles R Greathouse IV_, Sep 19 2012
%t A007962 nmax = 100; p = pq = pqr = {}; u = 9;
%t A007962 Reap[For[n = 1, n <= nmax, n++, o = Prime[n+1]; p = Union[p, {o}]; pq = Union[pq, p+o]; pqr = Union[pqr, pq+o]; While[MemberQ[pqr, u], u += 2]; Sow[u-2]]][[2, 1]] (* _Jean-François Alcover_, Dec 19 2017, after _Rémy Sigrist_ *)
%o A007962 (PARI) See Links section.
%K A007962 nonn
%O A007962 1,1
%A A007962 R. Muller