%I #18 Mar 29 2021 08:01:40
%S 22,51,59,80,109,118,138,167,177,196,225,236,254,283,295,312,341,354,
%T 370,399,413,428,457,472,486,515,531,544,573,590,602,631,649,660,689,
%U 708,718,747,767,776,805,826,834,863,885,892,921,944,950,979,1003,1008
%N Numbers k such that numerator of Bernoulli(2*k) is divisible by 59, the second irregular prime.
%C Satisfies a(n) = 2*a(n-3) - a(n-6) for n < 67. - _Chai Wah Wu_, May 28 2016
%H Amiram Eldar, <a href="/A092221/b092221.txt">Table of n, a(n) for n = 1..6450</a> (terms 1..1000 from Joerg Arndt)
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/BernoulliNumber.html">Bernoulli Number</a>.
%t Select[ Range[ 1036], Mod[ Numerator[ BernoulliB[2# ]], 59] == 0 &]
%o (Python)
%o from sympy import bernoulli
%o A092221_list = [n for n in range(10**3) if not bernoulli(2*n).p % 59] # _Chai Wah Wu_, May 28 2016
%o (PARI) for(n=0, 10^3, if( numerator(bernfrac(2*n))%59==0, print1(n, ", ") ) ); \\ _Joerg Arndt_, May 29 2016
%Y Cf. A000928, A091216, A092222, A092223, A092224, A092225, A092226, A092227, A092228, A092229, A092231.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Feb 25 2004