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Numbers with relatively many divisors
From OeisWiki
Contents
Definition
The number is in the sequence iff
where tau(n) is the number of divisors of n.
This definition gives the sequence (A??????) which is not yet in the OEIS
- {2, 3, 4, 5, 6, 8, 9, 10, 12, 16, 18, 20, 24, 30, 36, 40, 42, 48, 60, 72, 84, 90, 96, 108, 120, ...
Table giving the above sequence (Cf. A000005 for tau(n))
n tau(n) tau(n) - max[tau(1), ... tau(n-1)] 1 1 2 2 +1 3 2 0 4 3 +1 5 2 -1 6 4 +1 7 2 8 4 0 9 3 -1 10 4 0 11 2 12 6 +2 13 2 14 4 15 4 16 5 -1 17 2 18 6 0 19 2 20 6 0 21 4 22 4 23 2 24 8 +2 25 3 26 4 27 4 28 6 29 2 30 8 0 31 2 32 6 33 4 34 4 35 4 36 9 +1 37 2 38 4 39 4 40 8 -1 41 2 42 8 -1 43 2 44 6 45 6 46 4 47 2 48 10 +1 49 3 50 6 51 4 52 6 53 2 54 8 55 4 56 8 57 4 58 4 59 2 60 12 +2 61 2 62 4 63 6 64 7 65 4 66 8 67 2 68 6 69 4 70 8 71 2 72 12 0 73 2 74 4 75 6 76 6 77 4 78 8 79 2 80 10 81 5 82 4 83 2 84 12 0 85 4 86 4 87 4 88 8 89 2 90 12 0 91 4 92 6 93 4 94 4 95 4 96 12 0 97 2 98 6 99 6 100 9 101 2 102 8 103 2 104 8 105 8 106 4 107 2 108 12 0 109 2 110 8 111 4 112 10 113 2 114 8 115 4 116 6 117 6 118 4 119 4 120 16 +4
Table of interesting bases (with relatively many divisors)
Base | Sequence | OEIS
number |
Formula |
---|---|---|---|
2 | |||
3 | |||
4 | |||
5 | |||
6 | |||
8 | |||
9 | |||
10 | |||
12 | |||
16 | |||
18 | |||
20 | |||
24 | |||
30 | |||
36 | |||
40 | |||
42 | |||
48 | |||
60 | |||
72 | |||
84 | |||
90 | |||
96 | |||
108 | |||
120 |