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Search: id:A020731
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| A020731 |
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Numbers n for which number of distinct prime divisors of C(n,k) has maximum at k = n/2. |
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4
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| 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 30, 31, 32, 33, 35, 36, 37, 39, 40, 41, 42, 43, 47, 48, 49, 50, 55, 56, 57, 58, 63, 64, 65, 66, 67, 68, 71, 72, 73, 75, 76, 80, 83, 84, 85, 89, 90, 96, 97, 98, 99, 100, 107, 108, 109, 119
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OFFSET
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1,2
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EXAMPLE
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For n=21 the number of prime divisors of {C(21,k)} is {0,2,4,4,4,4,5,5,6,6,6,6,6,6,5,5,4,4,4,4,2,0}, the maximal value of 6 occurring at the central position.
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CROSSREFS
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Cf. A001221, A048486, A048299, A048484, A019491.
Sequence in context: A052382 A055572 A052040 this_sequence A090274 A032898 A131058
Adjacent sequences: A020728 A020729 A020730 this_sequence A020732 A020733 A020734
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KEYWORD
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nonn
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu)
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