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%I #7 Sep 20 2024 06:43:03
%S 39,63,71,79,87,95,111,119,127,135,143,151,156,159,167,175,183,191,
%T 199,207,215,223,231,239,247,252,255,263,271,279,284,287,295,303,311,
%U 316,319,327,335,343,348,351,359,367,375,380,383,391,399,407,415,423,431
%N Numbers that are the sum of 4 but no fewer nonzero squares and admit a representation with 4 distinct squares.
%C Intersection of A004215 and A004433.
%e 39 is a term, since it requires 4 squares to be represented and admits the representation 39 = 5^2 + 3^2 + 2^2 + 1^2.
%e 30 is not a term, although it can be represented as a sum of 4 different squares 30 = 4^2+ 3^2 + 2^2 + 1^2 also admits a representation as a sum of 3 squares: 30 = 5^2 + 2^2 + 1^2.
%e 7 is not a term, since although it requires 4 squares to be represented as follows 7 = 2^2 + 1^2 + 1^2 + 1^2, it is noted that 1 is used on more than one occasion.
%Y Cf. A004215, A004433.
%K nonn
%O 1,1
%A _Gonzalo Martínez_, Aug 26 2024