A354777 Irregular triangle read by rows: T(n,k) is the number of integer quadruples (u,v,w,x) such that u^2+v^2+w^2+x^2 = n and u+v+w+x = k (n>=0, 0 <= k <= A307531(n)).
1, 0, 4, 12, 0, 6, 0, 12, 0, 4, 6, 0, 8, 0, 1, 0, 12, 0, 12, 24, 0, 24, 0, 12, 0, 16, 0, 12, 0, 4, 12, 0, 0, 0, 6, 0, 24, 0, 16, 0, 12, 24, 0, 30, 0, 24, 0, 6, 0, 12, 0, 24, 0, 12, 8, 0, 24, 0, 12, 0, 8, 0, 24, 0, 12, 0, 16, 0, 4, 48, 0, 24, 0, 24, 0, 24, 0, 36, 0, 24, 0, 24, 0, 12, 6, 0, 0, 0, 8, 0, 0, 0, 1, 0, 12, 0, 36, 0, 12, 0, 12
Offset: 0
Examples
The triangle begins: [1], [0, 4], [12, 0, 6], [0, 12, 0, 4], [6, 0, 8, 0, 1], [0, 12, 0, 12], [24, 0, 24, 0, 12], [0, 16, 0, 12, 0, 4], [12, 0, 0, 0, 6], [0, 24, 0, 16, 0, 12], [24, 0, 30, 0, 24, 0, 6], [0, 12, 0, 24, 0, 12], [8, 0, 24, 0, 12, 0, 8], [0, 24, 0, 12, 0, 16, 0, 4], [48, 0, 24, 0, 24, 0, 24], [0, 36, 0, 24, 0, 24, 0, 12], [6, 0, 0, 0, 8, 0, 0, 0, 1], [0, 12, 0, 36, 0, 12, 0, 12], [36, 0, 48, 0, 48, 0, 30, 0, 12], ... T(4,2) = 8 from the solutions (u,v,w,x) = (2,0,0,0) (4 such) and (1,1,1,-1) (4 such).
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