This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A110071 #15 Jul 22 2024 03:35:41
%S A110071 0,4,290,11387,1656281,538311474096
%N A110071 Numbers n such that n = pi(d_1!!*d_2!!*...*d_k!!) where d_1 d_2 ... d_k is the decimal expansion of n.
%C A110071 No other terms below 10^14. - _Max Alekseyev_, Jul 21 2024
%e A110071 11387 is in the sequence because 11387 = pi(1!!*1!!*3!!*8!!*7!!).
%t A110071 Do[h = IntegerDigits[n]; l = Length[h]; If[n == PrimePi[ Product[h[[k]]!!, {k, l}]], Print[n]], {n, 0, 50000}]
%Y A110071 Cf. A000720, A006882, A097655, A110070, A110072.
%K A110071 base,hard,more,nonn
%O A110071 1,2
%A A110071 _Farideh Firoozbakht_, Jul 22 2005
%E A110071 a(5) added by _Farideh Firoozbakht_, Dec 02 2007
%E A110071 a(6) from _Max Alekseyev_, Jul 21 2024