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%I #15 Jul 22 2024 03:35:41
%S 0,4,290,11387,1656281,538311474096
%N 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 No other terms below 10^14. - _Max Alekseyev_, Jul 21 2024
%e 11387 is in the sequence because 11387 = pi(1!!*1!!*3!!*8!!*7!!).
%t Do[h = IntegerDigits[n]; l = Length[h]; If[n == PrimePi[ Product[h[[k]]!!, {k, l}]], Print[n]], {n, 0, 50000}]
%Y Cf. A000720, A006882, A097655, A110070, A110072.
%K base,hard,more,nonn
%O 1,2
%A _Farideh Firoozbakht_, Jul 22 2005
%E a(5) added by _Farideh Firoozbakht_, Dec 02 2007
%E a(6) from _Max Alekseyev_, Jul 21 2024
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