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A174908
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Numbers n such that the sum of the 4th powers of their digits > n.
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1
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2, 3, 4, 5, 6, 7, 8, 9, 12, 13, 14, 15, 16, 17, 18, 19, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73
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listen;
history;
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internal format)
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OFFSET
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1,1
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COMMENTS
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The sequence is finite and contains 5832 numbers. If n > 19999, sum of 4th powers of digits < n (see reference).
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REFERENCES
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J.M. De Koninck, Ces nombres qui nous fascinent. Entry 19999 p.212. Ellipses 2008.
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LINKS
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EXAMPLE
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73 is in the sequence because 7^4 + 3^4 = 2482 > 73.
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MAPLE
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with(numtheory):k:=0:for n from 1 to 20000 do:l:=length(n):n0:=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^4:od: if s>n then k:=k+1:printf(`%d, `, n):else fi:od:print(k):
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CROSSREFS
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KEYWORD
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nonn,easy,base,fini,full
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AUTHOR
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STATUS
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approved
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