A090126 Distinct values of denominators of Bernoulli numbers B(2n) in order of their appearance as n grows.

6, 30, 42, 66, 2730, 510, 798, 330, 138, 870, 14322, 1919190, 13530, 1806, 690, 282, 46410, 1590, 354, 56786730, 64722, 4686, 140100870, 3318, 230010, 498, 3404310, 61410, 272118, 1410, 4501770, 33330, 4326, 642, 209191710, 1518, 1671270, 1770

Offset

1,1

Links

R. J. Mathar, Table of n, a(n) for n = 1..842

Mathematica

t=Table[Denominator[BernoulliB[2*w]], {w, 1, 100}] s=Sort[t]; u=Union[t]; Length[u] Table[Count[s, Part[u, j]], {j, 1, Length[u]}] g=Table[Min[Flatten[Position[t, Part[u, j]]]], {j, 1, Length[u]}]; uu=Union[g]; Table[Part[t, Part[uu, j]], {j, 1, Length[g]}]
t = Table[Denominator[BernoulliB[n]], {n, 2, 3000, 2}]; For[n = 1, n <= Length[t], n++, p = Position[t, t[[n]]] // Rest; t = Delete[t, p]]; t (* Jean-François Alcover, Oct 14 2014 *)
DeleteDuplicates[Denominator[BernoulliB[2*Range[100]]]] (* Harvey P. Dale, May 27 2020 *)

Crossrefs

Cf. A027641, A027642.

Sequence in context: A080289 A175907 A114649 * A291566 A326580 A070195

Adjacent sequences: A090123 A090124 A090125 * A090127 A090128 A090129

Keyword

nonn

Author

Labos Elemer, Jan 16 2004

Status

approved