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A281962
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Least k such that k^n - 1 is a totient number (A002202), or 0 if no such k exists.
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1
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2, 3, 7, 3, 25, 5, 49, 3, 17, 5, 13, 3, 41, 7, 5, 3, 13, 5, 25, 3, 25, 5, 53, 3, 9, 9, 25, 3, 29, 3, 81, 3, 9, 15, 5, 3, 13, 5, 13, 3, 33, 5, 49, 3, 5, 9, 25, 3, 9, 3, 9, 3, 81, 5, 5, 3, 25, 7, 49, 3, 13, 9, 13, 3, 13, 3
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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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a(5) = 25 because 25^5 - 1 = 5^10 - 1 = 9765624 is a totient number and 25 is the least number with this property.
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PROG
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(PARI) a(n) = my(k=1); while(!istotient(k^n-1), k++); k;
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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