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A181684
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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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0
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4, 8, 11, 29, 38, 43, 70, 74, 80, 89, 104, 112, 116, 139, 143, 166, 170, 178, 179, 182, 184, 205, 217, 223, 224, 235, 266, 271, 289, 298, 304, 322, 325, 334, 338, 344, 347, 370, 385, 392, 413, 433, 436, 454, 458, 476, 481, 487, 488, 493
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OFFSET
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1,1
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LINKS
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EXAMPLE
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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.
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MAPLE
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with(numtheory):for n from 1 to 500 do: l:=length(n^n) : n0:=n^n: s:=0:for
m from 1 to l do: q:=n0:u:=irem(q, 10):v:=iquo(q, 10): n0:=v :s:=s+u^3: od:if
type(s, prime)=true then printf(`%d, `, n):else fi:od:
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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