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A188914
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a(n) = n*n! + 1 = (n+1)! - n! + 1.
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3
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1, 2, 5, 19, 97, 601, 4321, 35281, 322561, 3265921, 36288001, 439084801, 5748019201, 80951270401, 1220496076801, 19615115520001, 334764638208001, 6046686277632001, 115242726703104001, 2311256907767808001, 48658040163532800001, 1072909785605898240001
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OFFSET
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0,2
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COMMENTS
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It is unknown if all numbers of the form n*n!+1 are squarefree. n*n!+1 is squarefree for 0 < n < 52. It is unknown if there exist infinitely many primes of the form n*n!+1. For primes in this sequence, see A049984.
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LINKS
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FORMULA
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MATHEMATICA
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Table[(n*Factorial[n])+1, {n, 0, 30}]
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PROG
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CROSSREFS
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KEYWORD
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nonn,easy,nice
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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