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Numbers n such that concatenating n and the sum of the digits of n raised to their own power (A045503) produces a prime.
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%I #5 Feb 16 2020 13:20:06

%S 1,34,41,43,52,60,67,85,101,110,113,122,126,128,146,148,150,155,168,

%T 175,184,186,191,202,208,212,234,241,252,267,287,300,355,397,404,423,

%U 432,445,469,511,602,606,620,627,634,641,656,680,685,750,762,793,806,919

%N Numbers n such that concatenating n and the sum of the digits of n raised to their own power (A045503) produces a prime.

%C 2^2560 produces a 782 digit prime (certified).

%C For purposes of this sequence, zero raised to the zero power = 1. - _Harvey P. Dale_, Feb 16 2020

%e a(5)=52 because 5^5 + 2^2 = 3129 and 523129 is prime.

%t cnsdQ[n_]:=Module[{idn=IntegerDigits[n]/.(0->1),c},c=Total[idn^idn];PrimeQ[n*10^IntegerLength[c]+c]]; Select[Range[1000],cnsdQ] (* _Harvey P. Dale_, Feb 16 2020 *)

%Y Cf. A045503.

%K base,easy,nonn

%O 1,2

%A _Jason Earls_, Jun 29 2005