A349275 - OEIS

%I #7 Nov 12 2021 21:56:41

%S 469,649,694,4469,4694,4699,4946,6499,6649,6694,9446,9466,9469,9946,

%T 44669,44966,44969,46469,46946,46969,46994,46999,49466,49649,49694,

%U 49699,49969,64469,64649,64669,64949,64994,66469,66494,66694,69449,69469,69494,69694,69949,94469,94669,94699,94969,96449,96494,96649,96946,96949,96994,99646,99649,444694

%N Semiprimes with only semiprime digits, each appearing at least once.

%C Each digits 4, 6, 9 occur at least once. Minimal difference is 3.

%o (PARI) is(n)=bigomega(n)==2 && Set(digits(n))==[4, 6, 9] \\ _Charles R Greathouse IV_, Nov 12 2021

%Y Cf. A001358.

%Y Subsequence of A107342.

%K nonn,base

%O 1,1

%A _Zak Seidov_, Nov 12 2021