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%I #11 Jul 17 2024 16:16:53
%S 1,4,10,20,33,51,69,94,122,157,187,233,273,316,373,432,485,558,614,
%T 694,770,849,915,1019,1108,1205,1304,1410,1504,1640,1742,1872,1997,
%U 2121,2245,2410,2534,2678,2821,2994,3136,3320,3472,3647,3820,3993,4157,4393,4558,4757,4963,5186,5360,5593
%N Number of distinct sums i^2 + j^2 + k^2 for 1<=i<=j<=k<=n.
%o (PARI) a(n) = my(v=vector(3*n^2)); for(i=1, n, for(j=i, n, for(k=j, n, v[i^2+j^2+k^2]+=1))); sum(i=1, #v, v[i]>0);
%o (Python)
%o def A374715(n): return len({i**2+j**2+k**2 for i in range(1,n+1) for j in range(i,n+1) for k in range(j,n+1)}) # _Chai Wah Wu_, Jul 17 2024
%Y Cf. A061786, A374716.
%K nonn
%O 1,2
%A _Seiichi Manyama_, Jul 17 2024
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