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A115078 Numbers n such that n = prime(1 + d_1)*prime(1 + d_2)*...*prime(1 + d_k), where d_1 d_2 ... d_k is the decimal expansion of n. 0
171, 290, 2145, 3381, 74613, 10664845620, 14771330561681694, 2744819721528289762500 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(9), if it exists, must have more than 32 digits.

a(9) > 10^37 if it exists. - Chai Wah Wu, Aug 12 2017

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

a(2)=290 because 290 = p(1+2)*p(1+9)*p(1+0) = 5*29*2.

MATHEMATICA

t={}; Do[If[n==Times@@Prime[1+IntegerDigits@n], Print[n]; AppendTo[t, n]], {n, 10^5}]; t

PROG

(PARI) is(n) = my(d=digits(n)); n==prod(i=1, #d, prime(1+d[i])) \\ Felix Fröhlich, Aug 12 2017

CROSSREFS

Cf. A097227.

Sequence in context: A136365 A031900 A120819 * A183996 A062907 A266315

Adjacent sequences:  A115075 A115076 A115077 * A115079 A115080 A115081

KEYWORD

base,nonn

AUTHOR

Giovanni Resta, Jan 12 2006

STATUS

approved

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Last modified January 17 18:27 EST 2019. Contains 319250 sequences. (Running on oeis4.)