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%I #37 Jan 11 2019 11:46:19
%S 1,2,6,30,42,66,2730,14322,1919190,56786730,140100870,209191710,
%T 2328255930,2381714790,7225713885390,9538864545210,21626561658972270,
%U 446617991732222310,115471236091149548610,5145485882746933233510,14493038256293268734790
%N Incrementally largest denominators of the Bernoulli numbers.
%H Daniel Suteu, <a href="/A100194/b100194.txt">Table of n, a(n) for n = 1..85</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/BernoulliNumber.html">Bernoulli Number</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Von_Staudt%E2%80%93Clausen_theorem">Von Staudt-Clausen theorem</a>
%t 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 *)
%o (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))
%o lista(n) = { my(m=0); for(k=0, n, my(d=b(k)); if(d>m, m=d; print1(d, ", "))); }
%o lista(1000); \\ _Daniel Suteu_, Dec 22 2018
%Y Cf. A100195, A000367/A002445.
%K nonn
%O 1,2
%A _Eric W. Weisstein_, Nov 08 2004
%E a(21) from _Seiichi Manyama_, Jan 21 2017
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