cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A049794 a(n) = T(n,n-2), array T as in A049790.

This page as a plain text file.
%I A049794 #9 Sep 08 2022 08:44:58
%S A049794 1,2,3,6,11,16,25,31,44,53,66,79,97,108,130,148,168,187,214,233,265,
%T A049794 286,315,344,381,402,442,474,511,545,590,619,670,705,751,797,848,880,
%U A049794 940,988,1041,1087,1150,1192,1263,1311,1370,1431
%N A049794 a(n) = T(n,n-2), array T as in A049790.
%H A049794 G. C. Greubel, <a href="/A049794/b049794.txt">Table of n, a(n) for n = 3..1000</a>
%p A049794 seq( `if`(n<5, n-2, add(floor((n-2)/floor((n-4)/j)), j=1..n-4)), n=3..60); # _G. C. Greubel_, Dec 10 2019
%t A049794 Table[If[n<5, n-2, Sum[Floor[(n-2)/Floor[(n-4)/j]], {j,n-4}]], {n, 3,60}] (* _G. C. Greubel_, Dec 10 2019 *)
%o A049794 (PARI) a(n) = if(n<5, n-2, sum(j=1,n-4, (n-2)\((n-4)\j)) );
%o A049794 vector(60, n, a(n+2) ) \\ _G. C. Greubel_, Dec 10 2019
%o A049794 (Magma) [n lt 5 select n-2 else (&+[Floor((n-2)/Floor((n-4)/j)): j in [1..n-4]]): n in [3..60]]; // _G. C. Greubel_, Dec 10 2019
%o A049794 (Sage)
%o A049794 def a(n):
%o A049794     if (n<5): return n-2
%o A049794     else: return sum(floor((n-2)/floor((n-4)/j)) for j in (1..n-4))
%o A049794 [a(n) for n in (3..60)] # _G. C. Greubel_, Dec 10 2019
%o A049794 (GAP)
%o A049794 a:= function(n)
%o A049794     if n<5 then return n-2;
%o A049794     else return Sum([1..n-4], j-> Int((n-2)/Int((n-4)/j)) );
%o A049794     fi; end;
%o A049794 List([3..60], n-> a(n) ); # _G. C. Greubel_, Dec 10 2019
%Y A049794 Cf. A049790, A049791, A049792, A049793, A049795, A049796.
%K A049794 nonn
%O A049794 3,2
%A A049794 _Clark Kimberling_