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Triangle read by rows: T(n,k) (n>=k>=1) = f(n,n-k+1) where f(n,k) = round((n/k)*round(n/k)).
9

%I #12 Dec 02 2020 07:39:42

%S 1,1,4,1,3,9,1,1,4,16,1,1,3,8,25,1,1,3,4,9,36,1,1,1,4,5,14,49,1,1,1,3,

%T 4,8,16,64,1,1,1,3,4,5,9,23,81,1,1,1,1,3,4,8,10,25,100,1,1,1,1,3,4,4,

%U 8,15,33,121,1,1,1,1,3,3,4,5,9,16,36,144,1,1,1,1,1,3,4,4,8,10,17,46,169

%N Triangle read by rows: T(n,k) (n>=k>=1) = f(n,n-k+1) where f(n,k) = round((n/k)*round(n/k)).

%H Robert J. McEliece and Herbert Taylor, <a href="https://doi.org/10.1016/0097-3165(73)90069-1">Covering tori with squares</a>, Journal of Combinatorial Theory, Series A 14.1 (1973): 119-124.

%e Triangle begins:

%e 1,

%e 1, 4,

%e 1, 3, 9,

%e 1, 1, 4, 16,

%e 1, 1, 3, 8, 25,

%e 1, 1, 3, 4, 9, 36,

%e 1, 1, 1, 4, 5, 14, 49,

%e 1, 1, 1, 3, 4, 8, 16, 64,

%e 1, 1, 1, 3, 4, 5, 9, 23, 81,

%e 1, 1, 1, 1, 3, 4, 8, 10, 25, 100,

%e 1, 1, 1, 1, 3, 4, 4, 8, 15, 33, 121,

%e 1, 1, 1, 1, 3, 3, 4, 5, 9, 16, 36, 144,

%e 1, 1, 1, 1, 1, 3, 4, 4, 8, 10, 17, 46, 169,

%e ...

%Y Cf. A331145-A331153.

%K nonn,tabl

%O 1,3

%A _N. J. A. Sloane_, Jan 14 2020