cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A362506 a(n) is the least x >= 0 such that A362505(n) = x * y for some y with the same set of decimal digits as x.

Original entry on oeis.org

0, 1, 2, 3, 1, 4, 5, 6, 2, 7, 8, 9, 3, 10, 1, 11, 12, 13, 4, 14, 15, 12, 16, 5, 17, 18, 19, 6, 20, 13, 21, 2, 22, 23, 7, 14, 24, 25, 26, 8, 27, 23, 15, 28, 29, 9, 30, 31, 16, 3, 10, 24, 10, 32, 33, 10, 1, 34, 17, 11, 35, 36, 25, 12, 37, 38, 12, 18, 34, 12, 13
Offset: 1

Views

Author

Rémy Sigrist, Apr 23 2023

Keywords

Examples

			The first terms, alongside the corresponding y and A362505(n), are:
  n   a(n)  y    A362505(n)
  --  ----  ---  ----------
   1     0    0           0
   2     1    1           1
   3     2    2           4
   4     3    3           9
   5     1   11          11
   6     4    4          16
   7     5    5          25
   8     6    6          36
   9     2   22          44
  10     7    7          49
  11     8    8          64
  12     9    9          81
  13     3   33          99
  14    10   10         100
  15     1  111         111
		

Crossrefs

Cf. A362505.

Programs

  • PARI
    { print1(0); for (k = 1, 1469, fordiv (k, x, if (Set(digits(x)) == Set(digits(k/x)), print1 (", "x); break))) }
    
  • Python
    from sympy import divisors
    from itertools import count
    def agen(): # generator of terms
        yield 0
        for n in count(1):
            for x in divisors(n):
                if set(str(x)) == set(str(n//x)):
                    yield x
                    break
    print(list(islice(agen(), 71))) # Michael S. Branicky, Apr 23 2023