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%I #18 Apr 12 2023 09:17:21
%S 0,0,1,4,10,20,35,20,39,48,57,58,61,58,95,110,140,114,159,186,205,172,
%T 160,134,203,206,252,216,288,262,265,280,281,260,371,354,381,282,382,
%U 430,454,410,425,392,528,510,528,466,568,628,593,626,629,594,666,684,775
%N Antidiagonal sums of A336225.
%H Stefano Spezia, <a href="/A362072/b362072.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) = Sum_{k=1..n} A007953(k*(n-k)). - _Andrew Howroyd_, Apr 08 2023
%t T[i_, j_]:=Total[IntegerDigits[i*j]]; Table[Sum[T[n-j, j],{j,0,n}],{n,0,56}]
%o (PARI) a(n) = sum(k=1, n, sumdigits(k*(n-k))) \\ _Andrew Howroyd_, Apr 08 2023
%Y Cf. A003991, A007953, A336225, A353128.
%K nonn,base,look
%O 0,4
%A _Stefano Spezia_, Apr 08 2023