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.

A097368 Least term in row n of the Fibonacci regression array in A097367.

Original entry on oeis.org

1, 1, 2, 1, 2, 2, 1, 3, 2, 2, 3, 1, 3, 3, 2, 4, 2, 3, 4, 1, 4, 3, 3, 5, 2, 4, 4, 2, 5, 3, 4, 5, 1, 5, 4, 3, 6, 3, 5, 5, 2, 6, 4, 4, 6, 2, 6, 5, 3, 7, 4, 5, 6, 1, 7, 5, 4, 7, 3, 6, 6, 3, 8, 5, 5, 7, 2, 7, 6, 4, 8, 4, 6, 7, 2, 8, 6, 5, 8, 3, 7, 7, 4, 9, 5, 6, 8, 1, 8, 7, 5, 9, 4, 7, 8, 3, 9, 6, 6, 9, 3, 8, 8, 5, 10, 5
Offset: 2

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Author

Clark Kimberling, Aug 09 2004

Keywords

Comments

From Robert Israel, Jan 20 2018: (Start)
a(n) = 1 if and only if n is in A000045.
a(n) = 2 if and only if n >= 4 is in A000032 or 2*A000045.
a(m*n) <= m*a(n). (End)

Examples

			Row 8 of the array in A097367 is 7 6 5 4 1 4 6, of which the least term is T(8,5)=1.
		

Crossrefs

Programs

  • Maple
    T:= proc(n,k)
      local s,t,u;
       s:= n; t:= k;
       do
         u:= s-t;
         if u <= 0 then return t fi;
         s:= t;
         t:= u;
       od;
    end proc:
    f:= n -> min(seq(T(n,k),k=1..n-1)):
    map(f, [$2..200]); # Robert Israel, Jan 19 2018
  • Mathematica
    f[n_] := Fibonacci[n]; d[n_, k_, 1] := n; d[n_, k_, 2] := k;
    d[n_, k_, j_] := ((-1)^j) (k*f[j - 1] - n*f[j - 2]);
    s[n_, k_] := Select[Range[100], d[n, k, # + 1] <= 0 &, 1];
    t = Table[d[n, k, s[n, k]], {n, 2, 20}, {k, 1, n - 1}];  (* A097367 array *)
    Flatten[t]  (* A097367 sequence *)
    Table[Min[Flatten[Table[d[n, k, s[n, k]], {k, 1, n - 1}]]], {n, 2, 100}]  (* A097368 *)
    (* Clark Kimberling, Oct 14 2016 *)

Extensions

a(46) = 6 inserted by Clark Kimberling, Oct 14 2016