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A181683
Numbers n such that the sum of the square of digits of n^n is a prime.
0
3, 6, 7, 11, 20, 29, 30, 38, 56, 63, 89, 114, 124, 131, 139, 140, 176, 184, 192, 195, 198, 208, 214, 215, 223, 243, 300, 301, 331, 337, 345, 359, 372, 377, 388, 393, 407, 411, 451, 455, 459, 461, 476, 482, 483, 487, 506, 508, 516, 523, 536
OFFSET
1,1
EXAMPLE
6 is in the sequence because 6^6 = 46656 and 4^2 + 6^2 + 6^2 + 5^2 + 6^2 =
149 is a prime.
MAPLE
with(numtheory):for n from 1 to 540 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^2: od:if
type(s, prime)=true then printf(`%d, `, n):else fi:od:
CROSSREFS
Sequence in context: A258233 A015819 A298794 * A084125 A053478 A269363
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Nov 17 2010
STATUS
approved