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A115078
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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.
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0
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OFFSET
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1,1
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COMMENTS
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a(9), if it exists, must have more than 32 digits.
a(9) > 10^37 if it exists. - Chai Wah Wu, Aug 12 2017
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LINKS
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Table of n, a(n) for n=1..8.
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EXAMPLE
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a(2)=290 because 290 = p(1+2)*p(1+9)*p(1+0) = 5*29*2.
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MATHEMATICA
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t={}; Do[If[n==Times@@Prime[1+IntegerDigits@n], Print[n]; AppendTo[t, n]], {n, 10^5}]; t
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PROG
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(PARI) is(n) = my(d=digits(n)); n==prod(i=1, #d, prime(1+d[i])) \\ Felix Fröhlich, Aug 12 2017
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CROSSREFS
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Cf. A097227.
Sequence in context: A031900 A349097 A120819 * A183996 A062907 A266315
Adjacent sequences: A115075 A115076 A115077 * A115079 A115080 A115081
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KEYWORD
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base,nonn,more
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AUTHOR
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Giovanni Resta, Jan 12 2006
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STATUS
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approved
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