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A073819
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a(n) = prime(i) such that prime(i)*(n+1-i) is maximized (1 <= i <= n).
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2
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2, 2, 2, 5, 5, 11, 11, 11, 11, 17, 17, 17, 17, 29, 29, 29, 29, 29, 37, 37, 37, 41, 41, 41, 41, 59, 59, 59, 59, 59, 59, 59, 67, 67, 67, 71, 71, 97, 97, 97, 97, 97, 97, 97, 97, 97, 97, 97, 97, 127, 127, 127, 127, 127, 127, 127, 127, 149, 149, 149, 149, 149, 149, 149, 149
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| 3 is the only n for which the maximum is not unique; a(3) could also be given as 3.
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FORMULA
| a(n) = A073818(n)/A073820(n).
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EXAMPLE
| For n = 5, we take the first 5 primes in ascending order and multiply them by the numbers from 5 to 1 in descending order: 2*5 = 10 3*4 = 12 5*3 = 15 7*2 = 14 11*1 = 11 The largest product is 15, so a(5) = 5.
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CROSSREFS
| Cf. A073818, A073820.
Sequence in context: A035643 A163946 A096403 * A190846 A066835 A123953
Adjacent sequences: A073816 A073817 A073818 * A073820 A073821 A073822
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KEYWORD
| easy,nonn
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AUTHOR
| David Wasserman (wasserma(AT)spawar.navy.mil), Aug 13 2002
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