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%I #5 Mar 30 2012 18:49:13
%S 1,1,4,20,41,104,479,1146,7603,16521,91146,188021,188021,1861979,
%T 14122396,43294271,203450521,203450521,5877278646,5900065104,
%U 16886393229
%N Least k for which Omega(6k-1) + Omega(6k+1) >= n.
%C a(22) <= 170499674479. a(23) <= 1307169596354. a(24) <= 3178914388021. a(25) <= 3178914388021. a(26) <= 43614705403646 [From _Donovan Johnson_, Feb 17 2010]
%e When k=1,2 and 3, Omega(6k-1) + Omega(6k+1) = 2. When k=4, Omega(6k-1) + Omega(6k+1) = 3, so a(3)=4.
%t Maxie=0; For[x=6, x<10000001, x+=6,S=0;T=0; For[k=1, k< Length[FactorInteger[x-1]]+1,k++,S+= FactorInteger[x-1][[k]][[2]]]; For[m=1, m< Length[FactorInteger[x+1]]+1,m++,T+= FactorInteger[x+1][[m]][[2]]]; If[S+T>Maxie,Print[x/6," ",S+T];Maxie=S+T]]
%Y Cf. A145193
%K nonn
%O 1,3
%A _Arran Fernandez_, Oct 03 2008
%E a(15)-a(21) from _Donovan Johnson_, Feb 17 2010
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