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A025380 Numbers that are the sum of 4 distinct nonzero squares in exactly 5 ways. 2

%I #16 Nov 20 2023 00:03:53

%S 126,150,170,186,219,225,230,242,249,250,261,267,274,275,278,287,295,

%T 297,305,311,314,319,321,322,323,325,343,346,347,361,377,379,383,401,

%U 419,421,427,437,457,463,467,468,493,500,504,509,517,523,524,577,600,680,724,744

%N Numbers that are the sum of 4 distinct nonzero squares in exactly 5 ways.

%H Robert Israel, <a href="/A025380/b025380.txt">Table of n, a(n) for n = 1..114</a>

%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>

%F {n: A025443(n) = 5}. - _R. J. Mathar_, Jun 15 2018

%p N:= 100000: # for terms <= N

%p G:= mul(1+x^(i^2)*y, i=1..floor(sqrt(N))):

%p G4:= series(coeff(G,y,4),x,N+1):

%p select(t -> coeff(G4,x,t) = 5, [$1..N]): # _Robert Israel_, Nov 19 2023

%Y Cf. A025389, A025361.

%K nonn

%O 1,1

%A _David W. Wilson_

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Last modified April 19 12:14 EDT 2024. Contains 371792 sequences. (Running on oeis4.)