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.

Showing 1-4 of 4 results.

A174356 (-1)^(n+1)*n*A174276(n).

Original entry on oeis.org

0, 2, -12, 90, -280, 1050, -13860, 70070, -48048, 4594590, -4618900, 106696590, -382444920, 966735770, -3123300180, 97045398450, -97241449760, 3409528332210, -3610088822340, 9399601637426, -13492251154200
Offset: 0

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Author

Paul Curtz, Mar 17 2010

Keywords

Comments

The sequence obeys a(n) = A174289(n) - A174290(n), a formula that might be compared to A164869(n) = n*A027642(n) = A164558(n)-A164555(n).

A174289 Numerator of the n-th term of the inverse binomial transform of 1, 1/2, B_4, B_6, B_8,..., a modified Bernoulli sequence.

Original entry on oeis.org

1, -1, 1, -1, 11, -137, 4157, -44879, 74351, -23262859, 113428851, -18122193779, 593728889477, -17199344405209, 773610521462677, -398027397442098469, 7730820046943979149, -6072430937404995879629, 164713122370768078443379
Offset: 0

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Author

Paul Curtz, Mar 15 2010

Keywords

Comments

The denominators are in A174276. The input sequence starts 1, 1/2, 1/6, -1/30, 1/42....
The inverse binomial transform generates 1, -1/2, 1/6, -1/30, 11/70, -137/210, 4157/2310,...

Crossrefs

Programs

  • Maple
    read("transforms") ;
    L := [1,1/2,seq(bernoulli(2*i),i=1..30)] ;BINOMIALi(L) ; apply(numer,%) ; # R. J. Mathar, Dec 02 2010
  • Mathematica
    b[0]=1; b[1]=1/2; b[n_] := BernoulliB[2n-2]; a[n_] := Sum[(-1)^(n-k)*Binomial[n, k]*b[k], {k, 0, n}]; Table[a[n], {n, 0, 18}] // Numerator (* Jean-François Alcover_, Aug 09 2012 *)

A174290 Numerators of the inverse binomial transform of the sequence of nonzero Bernoulli numbers.

Original entry on oeis.org

1, -3, 13, -91, 291, -1187, 18017, -114949, 122399, -27857449, 118047751, -18228890369, 594111334397, -17200311140979, 773613644762857, -398027494487496919, 7730820144185428909, -6072430940814524211839
Offset: 0

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Author

Paul Curtz, Mar 15 2010

Keywords

Comments

The sequence of nonzero Bernoulli numbers is B(0), B(1), B(2), B(4), B(6) etc. Its inverse Bernoulli transform is 1, -3/2, 13/6, -91/30, 291/70, -1187/210, 18017/2310,... The current sequence is defined by extracting the numerators.

Crossrefs

Cf. A174276 (denominators), A174289.

Programs

  • Maple
    read("transforms") ;
    A174290 := proc(n) [1, -1/2, seq(bernoulli(2*i), i=1..30)] ; BINOMIALi(%) ; numer(op(n+1,%)) ; end proc:
    seq(A174290(n),n=0..30) ; # R. J. Mathar, Jan 21 2011

A176546 Bernoulli numerators A000367 with an additional 1 inserted to represent B_1.

Original entry on oeis.org

1, 1, 1, -1, 1, -1, 5, -691, 7, -3617, 43867, -174611, 854513, -236364091, 8553103, -23749461029, 8615841276005, -7709321041217, 2577687858367, -26315271553053477373, 2929993913841559, -261082718496449122051
Offset: 0

Views

Author

Paul Curtz, Apr 20 2010

Keywords

Comments

Equivalent to adding a 1 in front of A000367, or removing zeros in A164555.
(One could also remove zeros in A027641 which would flip the sign of a(1)).
The denominators are in A006954.

Examples

			B_0=1/1, B_1=1/2 "originally", B_2=1/6, B_4=-1/30, B_6=1/42,...
		

Crossrefs

Showing 1-4 of 4 results.