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.

A100649 a(n) is the numerator of 1 - Sum_{i=1..n} Bernoulli(i).

Original entry on oeis.org

1, 3, 4, 4, 41, 41, 47, 47, 289, 289, 1502, 1502, 15551, 15551, 5809, 5809, 3818123, 3818123, -76776508, -76776508, 934336415, 934336415, -127396984577, -127396984577, 6013822435553, 6013822435553, -149990624319638, -149990624319638, 167911724519886437, 167911724519886437
Offset: 0

Views

Author

N. J. A. Sloane, Dec 05 2004

Keywords

Examples

			1, 3/2, 4/3, 4/3, 41/30, 41/30, 47/35, 47/35, 289/210, 289/210, 1502/1155, 1502/1155, 15551/10010, 15551/10010, 5809/15015, 5809/15015, 3818123/510510, 3818123/510510, ...
		

Crossrefs

Cf. A027641, A027642, A100650 (denominators).

Programs

  • Maple
    A100649 := proc(n) 1-add( bernoulli(i),i=1..n) ; numer(%) ; end proc: # R. J. Mathar, Jul 01 2011
  • Mathematica
    a[n_]:=Numerator[1-Sum[BernoulliB[i],{i,n}]]; Array[a,30,0] (* Stefano Spezia, Aug 25 2025 *)