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%I #9 Feb 16 2020 20:08:17
%S 1,2,4,5,6,7,8,10,11,12,13,14,16,17,18,19,22,23,24,25,27,28,29,30,31,
%T 33,34,35,38,39,40,41,44,45,46,47,49,50,51,52,55,56,58,60,61,62,64,65,
%U 66,67,68,71,72,73,76,77,78,79,81,82,84,85,87,88,92,93,94,97,98,99,101
%N Numbers that are not the sum of three positive heptagonal numbers.
%C Complement of A117105. This is to heptagonal numbers A000566,
%C as A007536 is to hexagonal numbers A000384,
%C as A003679 is to pentagonal numbers A000326,
%C and as A004214 is to squares A000290.
%C This sequence is presumably finite: what is its likely last element?
%C Last element appears to be a(1671) = 273118. - _Charles R Greathouse IV_, Sep 27 2010
%H Charles R Greathouse IV, <a href="/A180917/b180917.txt">Table of n, a(n) for n = 1..1671</a>
%Y Cf. A000290, A000326, A000384, A000566, A003679, A004214, A007536, A117105.
%K easy,nonn
%O 1,2
%A _Jonathan Vos Post_, Sep 23 2010