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A202450
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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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0, 1, 4, 21, 10, 69905, 2451, 1432028818087, 18166035, 72719023, 316138782904777094553940, 14747027341648947707567131341794256650861, 1801710500115237891740015, 37089922913701070144219234699757985931372002942260401897575393
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OFFSET
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0,3
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LINKS
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EXAMPLE
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a(3) = 21 because 21*3!! + 1 = 21*3+1 = 64 = 4^3.
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MATHEMATICA
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a={}; Do[k = 2; While[ !IntegerQ[(k^n - 1)/n!!], k++ ]; AppendTo[a, (k^n-1)/n!!], {n, 0, 14}]; 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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