OFFSET
0,1
COMMENTS
Is this sequence infinite? - David A. Corneth, Aug 17 2018
MATHEMATICA
om = Array[PrimeOmega, 1100000]; sp = Flatten@ Position[om, 2]; Table[ sp[[ SelectFirst[ Range[Length[sp] - 1], Count[Take[om, {sp[[#]], sp[[# + 1]]}], x_ /; x == 1] == j &, 0]]], {j, 0, 10}] (* Giovanni Resta, Aug 16 2018 *)
PROG
(Perl) use ntheory ":all";
my($l, $nextn, @C)=(4, 0);
forcomposites {
if (is_semiprime($_)) {
my $c = prime_count($l+1, $_-1);
if (!defined $C[$c]) {
$C[$c] = $l;
while (defined $C[$nextn]) { print "$nextn $C[$nextn]\n"; $nextn++; }
}
$l = $_;
}
} 5, 1e7; # Dana Jacobsen, Aug 16 2018
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Reinhard Zumkeller, Oct 08 2003
EXTENSIONS
a(11)-a(15) from Donovan Johnson, Mar 14 2010
a(16) from Giovanni Resta, Aug 17 2018
a(17) from Giovanni Resta, Aug 18 2018
STATUS
approved