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%I #21 Jun 09 2022 21:51:27
%S 2,5,7,8,11,12,13,14,17,18,19,20,22,23,24,26,27,29,30,31,32,33,34,35,
%T 37,38,39,40,41,42,43,44,46,47,48,50,51,52,53,54,56,57,58,59,60,61,62,
%U 63,65,67,68,69,70,71,72,73,74,75,76,77,79,80,82,83,84
%N Numbers that are neither triangular nor square.
%H Reinhard Zumkeller, <a href="/A242401/b242401.txt">Table of n, a(n) for n = 1..10000</a>
%F A010052(a(n)) + A010054(a(n)) = 0. - _Reinhard Zumkeller_, May 13 2014
%e 6 is not a term because it's triangular;
%e 9 is not a term because it's square.
%t With[{nn=90},Complement[Range[nn],Range[Floor[Sqrt[nn]]]^2,Accumulate[ Range[ Floor[(Sqrt[1+8nn]-1)/2]]]]] (* _Harvey P. Dale_, May 03 2022 *)
%o (Sage)
%o [x for x in [1..100] if not(is_square(x)) and not(is_triangular_number(x))] # _Tom Edgar_, May 13 2014
%o (Haskell)
%o a242401 n = a242401_list !! (n-1)
%o a242401_list = filter ((== 0) . a010054) a000037_list
%o -- _Reinhard Zumkeller_, May 13 2014
%Y Cf. A000217, A000290.
%Y Cf. A005214 (complement); intersection of A000037 and A014132.
%K nonn,easy
%O 1,1
%A _J. Lowell_, May 13 2014
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