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.

A007298 Sums of consecutive Fibonacci numbers.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 13, 16, 18, 19, 20, 21, 26, 29, 31, 32, 33, 34, 42, 47, 50, 52, 53, 54, 55, 68, 76, 81, 84, 86, 87, 88, 89, 110, 123, 131, 136, 139, 141, 142, 143, 144, 178, 199, 212, 220, 225, 228, 230, 231, 232, 233, 288, 322
Offset: 1

Views

Author

N. J. A. Sloane, Jan 02 2000

Keywords

Comments

Also the differences between two Fibonacci numbers, because the difference F(i+2) - F(j+1) equals the sum F(j) + ... + F(i). - T. D. Noe, Oct 17 2005; corrected by Patrick Capelle, Mar 01 2008

Crossrefs

Cf. A113188 (primes that are the difference of two Fibonacci numbers).
Cf. A219114 (numbers whose squares are here).

Programs

  • Maple
    isA007298 := proc(n)
        local i,Fi,j,Fj ;
        for i from 0 do
            Fi := combinat[fibonacci](i) ;
            for j from i do
                Fj :=combinat[fibonacci](j) ;
                if Fj-Fi = n then
                    return true;
                elif Fj-Fi > n then
                    break;
                end if;
            end do:
            Fj :=combinat[fibonacci](i+1) ;
            if Fj-Fi > n then
                return false;
            end if;
        end do:
    end proc:
    for n from 0 to 100 do
        if isA007298(n) then
            printf("%d,",n) ;
        end if;
    end do: # R. J. Mathar, May 25 2016
  • Mathematica
    Union[Flatten[Table[Fibonacci[n]-Fibonacci[i], {n, 14}, {i, n}]]] (* T. D. Noe, Oct 17 2005 *)
    isA007298[n_] := Module[{i, Fi, j, Fj}, For[i = 0, True, i++, Fi = Fibonacci[i]; For[j = i, True, j++, Fj = Fibonacci[j]; Which[Fj - Fi == n, Return@True, Fj - Fi > n, Break[]]]; Fj := Fibonacci[i + 1]; If[Fj - Fi > n, Return@False]]];
    Select[Range[0, 1000], isA007298] (* Jean-François Alcover, Nov 16 2023, after R. J. Mathar *)
  • PARI
    A130233(n)=log(sqrt(5)*n+1.5)\log((1+sqrt(5))/2)
    list(lim)=my(v=List([0]),F=vector(A130233(lim),i,fibonacci(i)),s,t); for(i=1,#F, s=0; forstep(j=i,1,-1, s+=F[j]; if(s>lim, break); listput(v,s))); Set(v) \\ Charles R Greathouse IV, Oct 06 2016

Formula

log a(n) >> sqrt(n). - Charles R Greathouse IV, Oct 06 2016