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%I #27 Jan 17 2024 05:24:32
%S 0,1,4,5,10,11,14,20,21,24,30,35,36,39,45,55,56,57,60,66,76,84,85,88,
%T 91,94,104,119,120,121,124,130,140,155,165,166,169,175,176,185,200,
%U 204,220,221,224,230,240,249,255,276,285,286,287,290,296,304,306
%N Sum of 1 or 2 distinct tetrahedral numbers.
%H Robert Israel, <a href="/A102856/b102856.txt">Table of n, a(n) for n = 1..10000</a>
%p N:= 1000: # for terms <= N
%p R:= 0:
%p for i from 1 do
%p ti:= i*(i+1)*(i+2)/6;
%p if ti > N then break fi;
%p for j from 0 to i-1 do
%p v:= ti + j*(j+1)*(j+2)/6;
%p if v > N then break fi;
%p R:= R, v;
%p od;
%p od:
%p sort(convert({R},list)); # _Robert Israel_, Jan 16 2024
%t Module[{nn=12, tetra}, tetra=Table[(n(n+1)(n+2))/6, {n, nn}]; Union[ Total/@ Subsets[tetra, 2]]] (* _James C. McMahon_, Jan 12 2024 *)
%Y Cf. A000292, A010329, A104246, A102795-A102806, A102855, A102857, A102858, A334013.
%K nonn
%O 1,3
%A _Jud McCranie_, Mar 01 2005
%E a(1) = 0 prepended by _James C. McMahon_, Jan 15 2024
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