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A327785 Square array read by antidiagonals: A(n,k) = Sum_{d|n} (k/d), (n>=1, k>=0), where (m/n) is the Kronecker symbol.

%I A327785 #17 Sep 25 2019 17:02:14
%S A327785 1,1,1,1,2,1,1,1,2,1,1,0,0,3,1,1,1,1,1,2,1,1,0,2,1,0,4,1,1,1,0,1,0,0,
%T A327785 2,1,1,2,1,1,2,0,2,4,1,1,1,2,1,1,2,0,1,3,1,1,2,0,3,2,0,2,0,1,4,1,1,1,
%U A327785 1,1,0,1,0,1,1,0,2,1,1,0,2,3,0,4,0,0,3,0,0,6,1
%N A327785 Square array read by antidiagonals: A(n,k) = Sum_{d|n} (k/d), (n>=1, k>=0), where (m/n) is the Kronecker symbol.
%H A327785 Seiichi Manyama, <a href="/A327785/b327785.txt">Antidiagonals n = 1..100, flattened</a>
%e A327785 Square array begins:
%e A327785    1, 1, 1, 1, 1, 1, 1, 1, ...
%e A327785    1, 2, 1, 0, 1, 0, 1, 2, ...
%e A327785    1, 2, 0, 1, 2, 0, 1, 2, ...
%e A327785    1, 3, 1, 1, 1, 1, 1, 3, ...
%e A327785    1, 2, 0, 0, 2, 1, 2, 0, ...
%e A327785    1, 4, 0, 0, 2, 0, 1, 4, ...
%e A327785    1, 2, 2, 0, 2, 0, 0, 1, ...
%e A327785    1, 4, 1, 0, 1, 0, 1, 4, ...
%t A327785 A[n_, k_] := Sum[KroneckerSymbol[k, d], {d, Divisors[n]}];
%t A327785 Table[A[n - k, k], {n, 1, 13}, {k, n - 1, 0, -1}] // Flatten (* _Jean-François Alcover_, Sep 25 2019 *)
%Y A327785 Columns k=0..31 give A000012, A000005, A035185, A035186, A001227, A035187, A035188, A035189, A035185, A035191, A035192, A035193, A035194, A035195, A035196, A035197, A001227, A035199, A035200, A035201, A035202, A035203, A035204, A035205, A035188, A035207, A035208, A035186, A035210, A035211, A035212, A035213.
%Y A327785 Cf. A215200.
%K A327785 nonn,tabl
%O A327785 1,5
%A A327785 _Seiichi Manyama_, Sep 25 2019