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%I #5 May 01 2019 15:32:13
%S 1,7,27,27,33,81,117,125,125,131,251,275,275,311,335,335,349,493,493,
%T 613,613,637,637,697,697,727,871,991,999,1023,1143,1143,1191,1191,
%U 1215,1215,1281,1449,1569,1617,1737,1785,1785,1809,1889,1985,1985,2033,2033
%N a(n) = A175376(n^2).
%C Number of integer triples (x,y,z) satisfying x^4+y^4+z^4 <= n^2, -n <= x,y,z <= n.
%H Robert Israel, <a href="/A175377/b175377.txt">Table of n, a(n) for n = 0..10000</a>
%p N:= 100: # to get a(1)..a(N)
%p A:= Array(0..N):
%p for i from 0 while i^4 <= N^2 do
%p if i=0 then ai:= 1 else ai:= 2 fi;
%p for j from 0 while i^4 + j^4 <= N^2 do
%p if j=0 then aj:= 1 else aj:= 2 fi;
%p for k from 0 do
%p v:= ceil((i^4 + j^4 + k^4)^(1/2));
%p if v > N then break fi;
%p if k = 0 then ak:= 1 else ak:= 2 fi;
%p A[v..N]:= map(`+`,A[v..N] ,ai*aj*ak);
%p od od od:
%p convert(A,list); # _Robert Israel_, May 01 2019
%Y Cf. A055410, A175370.
%K nonn
%O 0,2
%A _R. J. Mathar_, Apr 24 2010
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