A100194 Incrementally largest denominators of the Bernoulli numbers.

1, 2, 6, 30, 42, 66, 2730, 14322, 1919190, 56786730, 140100870, 209191710, 2328255930, 2381714790, 7225713885390, 9538864545210, 21626561658972270, 446617991732222310, 115471236091149548610, 5145485882746933233510, 14493038256293268734790

Offset

1,2

Links

Daniel Suteu, Table of n, a(n) for n = 1..85

Eric Weisstein's World of Mathematics, Bernoulli Number

Wikipedia, Von Staudt-Clausen theorem

Mathematica

Reap[For[n = record = 0, n < 1000, n = n + 2, If[(d = Denominator[BernoulliB[n]]) > record, Sow[d]; record = d]]][[2, 1]] (* Jean-François Alcover, Nov 09 2012 *)

Prog

(PARI) b(n) = if((n==0) || (n>1 && n%2==1), 1, my(d=divisors(n)); prod(k=1, #d, if(isprime(d[k]+1), d[k]+1, 1))); \\ more efficient than denominator(bernfrac(n))
lista(n) = { my(m=0); for(k=0, n, my(d=b(k)); if(d>m, m=d; print1(d, ", "))); }
lista(1000); \\ Daniel Suteu, Dec 22 2018

Crossrefs

Cf. A100195, A000367/A002445.

Sequence in context: A265501 A090801 A166062 * A229882 A325986 A298759

Adjacent sequences: A100191 A100192 A100193 * A100195 A100196 A100197

Keyword

nonn

Author

Eric W. Weisstein, Nov 08 2004

Extensions

a(21) from Seiichi Manyama, Jan 21 2017

Status

approved