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a(n) = Sum_{k=1..n} T(n,k), array T as in A049765.
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%I #23 Sep 08 2022 08:44:58

%S 0,1,4,7,14,18,29,36,48,58,77,83,106,122,141,156,187,200,235,251,280,

%T 308,351,361,403,437,476,502,557,573,632,663,712,758,813,828,899,951,

%U 1010,1038,1117,1145,1228,1274,1329,1393,1484

%N a(n) = Sum_{k=1..n} T(n,k), array T as in A049765.

%H G. C. Greubel, <a href="/A049766/b049766.txt">Table of n, a(n) for n = 1..1000</a>

%p seq( add( `mod`(k, n) + `mod`(n, k), k = 1..n), n = 1..50); # _G. C. Greubel_, Dec 13 2019

%t T[n_, k_] := Mod[n, k] + Mod[k, n]; Map[Total[T[#, Range[#]]] &, Range[80]] (* _Carl Najafi_, Aug 24 2011 *)

%o (PARI) a(n) = sum(k=1, n, k%n + n%k); \\ _Michel Marcus_, Aug 22 2015

%o (Magma) [&+[ (k mod n) + (n mod k): k in [1..n]]: n in [1..50]]; // _G. C. Greubel_, Dec 13 2019

%o (Sage) [sum((k%n) + (n%k) for k in (1..n)) for n in (1..50)] # _G. C. Greubel_, Dec 13 2019

%o (GAP) List([1..50], n-> Sum([1..n], k-> (k mod n) + (n mod k)) ); # _G. C. Greubel_, Dec 13 2019

%Y Row sums of A049765.

%Y Cf. A049767, A049768.

%K nonn

%O 1,3

%A _Clark Kimberling_