OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
Filter:= proc(n) local F;
F:= ifactors(n)[2];
if max(seq(f[2], f=F)) > 1 or nops(F) < 4 then return false fi;
F:= map(t -> t[1], F);
convert(F, `+`) = 2*(max(F)+min(F));
end proc:
select(Filter, [$1..10^5]); # Robert Israel, Dec 31 2015
MATHEMATICA
Select[Range[50000], Max@@Last/@(fi=FactorInteger[#])==1&&Plus@@(pl=First/@fi)/2==pl[[1]]+pl[[-1]]&] (*Ray Chandler, Nov 14 2011*)
CROSSREFS
KEYWORD
nonn
AUTHOR
Ray Chandler, Nov 14 2011
STATUS
approved