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Numbers n such that the sum of the cube of digits of n^n is a prime.
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%I #7 Mar 30 2012 18:35:54

%S 4,8,11,29,38,43,70,74,80,89,104,112,116,139,143,166,170,178,179,182,

%T 184,205,217,223,224,235,266,271,289,298,304,322,325,334,338,344,347,

%U 370,385,392,413,433,436,454,458,476,481,487,488,493

%N Numbers n such that the sum of the cube of digits of n^n is a prime.

%e 8 is in the sequence because 8^8= 16777216 and 1^3 + 6^3 + 7^3 + 7^3 + 7^3 + 2^3 + 1^3 + 6^3 = 1471 is a prime.

%p with(numtheory):for n from 1 to 500 do: l:=length(n^n) : n0:=n^n: s:=0:for

%p m from 1 to l do: q:=n0:u:=irem(q,10):v:=iquo(q,10): n0:=v :s:=s+u^3: od:if

%p type(s,prime)=true then printf(`%d, `, n):else fi:od:

%K nonn,base

%O 1,1

%A _Michel Lagneau_, Nov 17 2010