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Template:Sequence of the Day for March 30
From OeisWiki
Intended for: March 30, 2012
Timetable
- First draft to be entered by December 30, 2011
- Draft to be reviewed by January 30, 2012
- Draft to be approved by February 29, 2012
Yesterday's SOTD * Tomorrow's SOTD
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A121023: Multiples of 3 containing a 3 in their decimal representation.
- { 3, 30, 33, 36, 39, 63, 93, 123, 132, 135, 138, 153, 183, 213, 231, ... }
The graph of this sequence is (roughly) self-similar: it has the same appearance when the scale is multiplied by 10.
The same can be generalized to multiples of any other numberd |
d |
d |
Another generalization is that of numbers containing some or all of their divisors as substrings in their decimal expansion, or simply the digits thereof. Relevant sequences include
- A092911: All divisors can be formed using the digits of the number.
- A239058: All divisors are a substring of the decimal expansion, which is the union of primes having a digit 1 (A208270).
and the more challenging
- A239060: Non-prime numbers having all divisors are a substring of the decimal expansion. (Of which the 4th term is not yet known!)