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A129917 Numbers n such that adding the sum of the digits of n to the product of n and the product of its digits yields a prime. 0

%I

%S 1,11,13,14,16,17,19,20,25,30,31,32,37,43,47,49,50,58,61,70,73,74,79,

%T 83,85,91,92,95,101,102,104,106,110,120,140,160,164,188,200,201,203,

%U 205,209,210,212,218,223,227,230,232,238,245,250

%N Numbers n such that adding the sum of the digits of n to the product of n and the product of its digits yields a prime.

%e The sum of the digits of 11 is 2, the product is 1. 1*11 +

%e 2 = 13 is a prime.

%e Therefore 11 is in the sequence.

%t Select[Range[1000], PrimeQ[ #*Times@@IntegerDigits[ # ] + Plus@@IntegerDigits[ # ]]&]

%K base,nonn,less

%O 1,2

%A _J. M. Bergot_, Jun 05 2007

%E Edited and extended by _Stefan Steinerberger_, Jun 14 2007

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Last modified December 5 20:39 EST 2021. Contains 349558 sequences. (Running on oeis4.)