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%I #20 May 11 2023 12:44:36
%S 171,290,2145,3381,74613,10664845620,14771330561681694,
%T 2744819721528289762500
%N Numbers k such that k = prime(1 + d_1)*prime(1 + d_2)*...*prime(1 + d_m), where d_1 d_2 ... d_m is the decimal expansion of k.
%C a(9), if it exists, must have more than 32 digits.
%C a(9) > 10^37 if it exists. - _Chai Wah Wu_, Aug 12 2017
%e 290 is a term because 290 = p(1+2)*p(1+9)*p(1+0) = 5*29*2.
%t t={};Do[If[n==Times@@Prime[1+IntegerDigits@n], Print[n];AppendTo[t, n]], {n, 10^5}];t
%o (PARI) is(n) = my(d=digits(n)); n==prod(i=1, #d, prime(1+d[i])) \\ _Felix Fröhlich_, Aug 12 2017
%Y Cf. A097227.
%Y Fixed points of A359802.
%K base,nonn,more
%O 1,1
%A _Giovanni Resta_, Jan 12 2006
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