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A141757 Even terms in A100933.

%I A141757 #4 Jan 21 2014 12:30:21
%S A141757 50,98,150,242,250,294,338,350,490,550,578,650,686,722,726,750,850,
%T A141757 950,1014,1050,1058,1078,1150,1210,1274,1450,1470,1550,1650,1666,1682,
%U A141757 1690,1694,1734,1750,1850,1862,1922,1950,2050,2058,2150,2166,2254,2350,2366
%N A141757 Even terms in A100933.
%p A141757 with(numtheory):
%p A141757 # For A100549: if n = prod_p p^e_p, then pp = largest prime <= 1 + max e_p
%p A141757 pp := proc(n) local f,m; option remember;
%p A141757 if (n = 1) then
%p A141757 return 1;
%p A141757 end if;
%p A141757 m := 1:
%p A141757 for f in op(2..-1,ifactors(n)) do
%p A141757 if (f[2] > m) then
%p A141757 m := f[2]:
%p A141757 end if;
%p A141757 end do;
%p A141757 prevprime(m+2);
%p A141757 end proc;
%p A141757 # For A100762: B = prod_{p <= pp(n)} p^e_p
%p A141757 B := proc(n) local v,f,pv; global pp; option remember;
%p A141757 pv := pp(n);
%p A141757 v := 1:
%p A141757 for f in op(2..-1,ifactors(n)) while f[1] <= pv do
%p A141757 v := v * f[1]^f[2];
%p A141757 end do;
%p A141757 return v;
%p A141757 end proc;
%p A141757 # For A100417: Bgood = (is pp(n) = pp(B(n))), that is, is B(n) enough to establish pp(n)?
%p A141757 Bgood := proc(n) global pp;
%p A141757 `if`(pp(B(n))=pp(n),true,false);
%p A141757 end proc;
%p A141757 # For A100933 and A141757:
%p A141757 t0:=select(not Bgood, [$1..3000]);
%p A141757 t1:=[];
%p A141757 for n from 1 to nops(t0) do
%p A141757 if t0[n] mod 2 = 0 then t1:=[op(t1),t0[n]]; fi; od: t1;
%K A141757 nonn
%O A141757 1,1
%A A141757 _David Applegate_ and _N. J. A. Sloane_, Sep 15 2008