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%I #8 Sep 08 2022 08:44:58
%S 1,2,4,9,13,22,27,39,47,61,71,91,100,122,137,160,175,205,220,253,272,
%T 304,326,368,386,427,455,497,523,575,598,651,683,733,768,830,856,918,
%U 959,1021,1056,1129,1162,1236,1281,1347,1393
%N a(n) = T(n,n-1), array T as in A049790.
%H G. C. Greubel, <a href="/A049793/b049793.txt">Table of n, a(n) for n = 2..1000</a>
%p seq( `if`(n=2, 1, add(floor((n-1)/floor((n-2)/j)), j=1..n-2)), n=2..60); # _G. C. Greubel_, Dec 10 2019
%t Table[If[n==2, 1, Sum[Floor[(n-1)/Floor[(n-2)/j]], {j,n-2}]], {n, 2,60}] (* _G. C. Greubel_, Dec 10 2019 *)
%o (PARI) a(n) = if(n==2, 1, sum(j=1,n-2, (n-1)\((n-2)\j)) );
%o vector(60, n, a(n+1) ) \\ _G. C. Greubel_, Dec 10 2019
%o (Magma) [n eq 2 select 1 else (&+[Floor((n-1)/Floor((n-2)/j)): j in [1..n-2]]): n in [2..60]]; // _G. C. Greubel_, Dec 10 2019
%o (Sage)
%o def a(n):
%o if (n==2): return 1
%o else: return sum(floor((n-1)/floor((n-2)/j)) for j in (1..n-2))
%o [a(n) for n in (2..60)] # _G. C. Greubel_, Dec 10 2019
%o (GAP)
%o a:= function(n)
%o if n=2 then return 1;
%o else return Sum([1..n-2], j-> Int((n-1)/Int((n-2)/j)) );
%o fi; end;
%o List([2..60], n-> a(n) ); # _G. C. Greubel_, Dec 10 2019
%Y Cf. A049790, A049791, A049792, A049794, A049795, A049796.
%K nonn
%O 2,2
%A _Clark Kimberling_
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