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A108880
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Alphabetically earliest number that is a product of exactly n primes.
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0
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8018018851, 8000000018, 8, 8018000018, 8018018886, 8018018085, 8018018808, 8000000008, 8018018000, 8018018048, 8018018816, 8018018176, 8018808000, 8018808832, 8018000000, 8018018304, 8018887680, 8018804736, 8018853888
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OFFSET
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1,1
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COMMENTS
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Conway and Guy note that 8018018851 is, alphabetically, the first prime number in the American system of large number terminology and term this "Knuth's number." We have "eight billion" alphabetically before "eighteen" or "eighty."
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REFERENCES
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Conway, J. H. and Guy, R. K. The Book of Numbers. New York: Springer-Verlag, p. 15, 1996.
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LINKS
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EXAMPLE
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n Alphabetically first n-almost prime
1 8018018851
2 8000000018 = 2 * 4000000009
3 8 = 2^3
4 8018000018 = 2 * 7 * 97 * 5904271
5 8018018886 = 2 * 3 * 19 * 6661 * 10559
6 8018018085 = 3 * 5 * 7 * 11 * 163 * 42589
7 8018018808 = 2^3 * 3 * 31 * 2161 * 4987
8 8000000008 = 2^3 * 7 * 11 * 13 * 19 * 52579
9 8018018000 = 2^4 * 5^3 * 127 * 31567
10 8018018048 = 2^8 * 43 * 728381
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CROSSREFS
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KEYWORD
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nonn,word
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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