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A216474
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Smallest k such that k*!n +1 is an n-th power.
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0
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3, 13, 455, 71, 93565703, 40765959421975394881, 27507928745358015883503, 4005456298012605183835102420301535996, 64381553566633030980078485248402475462864768, 67848687916710307026239471566668726955520894650602664910832487
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OFFSET
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2,1
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COMMENTS
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!n is a subfactorial number (A000166).
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LINKS
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EXAMPLE
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a(4) = 455 because 455*!4 + 1 = 455*9+1 = 4096 = 4^6.
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MATHEMATICA
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a={}; Do[k = 2; While[ !IntegerQ[(k^n - 1)/Subfactorial[n]], k++ ]; AppendTo[a, (k^n-1)/Subfactorial[n]], {n, 2, 11}]; a
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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