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.

A000052 1-digit numbers arranged in alphabetical order, then the 2-digit numbers arranged in alphabetical order, then the 3-digit numbers, etc.

Original entry on oeis.org

8, 5, 4, 9, 1, 7, 6, 3, 2, 0, 18, 80, 88, 85, 84, 89, 81, 87, 86, 83, 82, 11, 15, 50, 58, 55, 54, 59, 51, 57, 56, 53, 52, 40, 48, 45, 44, 49, 41, 47, 46, 43, 42, 14, 19, 90, 98, 95, 94, 99, 91, 97, 96, 93, 92, 17, 70, 78, 75, 74, 79, 71, 77, 76, 73, 72
Offset: 1

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Author

Keywords

Comments

This sequence uses standard US English names for numbers. - Daniel Forgues, May 11 2016
For example, standard US English writes out the number 101 as "one hundred one", whereas standard UK English writes it out as "one hundred and one" (see Links). - Jon E. Schoenfield, Dec 25 2016
Alphabetical order is with spaces removed/disregarded, else, as a first example, a(1003)=8018 ("eight thousand eighteen") would follow a(1004)=8800 ("eight thousand eight hundred") among others. - Michael S. Branicky, Aug 05 2021

Examples

			eight, five, four, nine, one, seven, six, three, two, zero, eighteen, etc.
Examples of spelling convention used for values above 99:
400: "four hundred"
726: "seven hundred twenty-six"
1992: "one thousand nine hundred ninety-two"
2202: "two thousand two hundred two"
101001: "one hundred one thousand one"
726726: "seven hundred twenty-six thousand seven hundred twenty-six"
101000001: "one hundred one million one"
		

Crossrefs

Cf. A001058.

Programs

  • Maple
    V:= [[$0..9],[$10..99],[$100..999]]:
    seq(op(V[i][sort(map(convert,V[i],english,'And'),
    output=permutation)]),i=1..3); # Robert Israel, Jun 17 2016
  • Mathematica
    Flatten@Join[{8, 5, 4, 9, 1, 7, 6, 3, 2, 0}, SortBy[Range[10^#, 10^(# + 1) - 1], StringReplace[IntegerName[#, "Words"], "," -> ""] &] & /@ Range[3]] (* Davin Park, Dec 25 2016 *)
  • Python
    from num2words import num2words
    def n2w(n):
      return num2words(n).replace(" and", "").replace(",", "").replace(" ", "")
    def agen(maxdigits):
      for d in range(1, maxdigits+1):
        yield from sorted(range(10**(d-1)-(d==1), 10**d), key=lambda x: n2w(x))
    print([an for an in agen(2)]) # Michael S. Branicky, Aug 05 2021

Extensions

Corrected by Davin Park, Dec 25 2016