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.

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A002810 Smallest number containing n syllables in UK English.

Original entry on oeis.org

1, 7, 11, 27, 77, 107, 111, 127, 177, 777, 1127, 1177, 1777, 7777, 11777, 27777, 77777, 107777, 111777, 127777, 177777, 777777, 1127777, 1177777, 1777777, 7777777, 11777777, 27777777, 77777777, 107777777, 111777777, 127777777, 177777777, 777777777
Offset: 1

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Author

Keywords

Comments

This sequence uses UK English as opposed to US English. a(6) = 107 since "one hundred and seven" has six syllables. - N. J. A. Sloane, Nov 24 2009
Because of this convention, we do not have A075774(a(n))=n, since A075774 uses US English, i.e., without the "trailing 'and'". All terms from a(6)=107 on will have this 'and', therefore A075774(a(n)) = n-1 for 5 < n < 18. From a(18)=107777 on, there is a second 'and', etc. See A045736 for the "American English" version, see A001167 for the analog considering the number of words. - M. F. Hasler, Nov 03 2013
From Bernard Schott, Feb 18 2019: (Start)
a(19) = 111777 is precisely the number used for Berry's paradox. In UK English the name of the number 111777 requires 19 syllables -- "one hundred and eleven thousand seven hundred and seventy-seven" -- and it's exactly the smallest number containing 19 syllables in UK English.
The paradox occurs when we consider that this integer is "the least integer not nameable in fewer than nineteen syllables" yet 111777 has just now been defined in eighteen syllables with this last sentence. So there is a contradiction, because the smallest integer expressible in no fewer than nineteen syllables can be expressed in eighteen syllables. This contradiction is Berry's paradox. (End)

Examples

			"One" has one syllable, therefore a(1)=1; a(2)=7 since "seven" is the least number to have two syllables; a(3)=11 because eleven is the first to have 3 syllables.
		

References

  • Rodolfo Kurchan, Mesmerizing Math Puzzles, by Sterling Publications, 2000, p. 18.
  • R. C. Penner, Discrete Mathematics, Proofs Techniques and Mathematical Structures, World Scientific, 1999, Reprinted 2001, p. 97.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
  • David Wells, The Penguin Dictionary of Curious and Interesting Numbers, Penguin Books, Revised edition, 1997, p. 171.

Crossrefs

Cf. A045736.

Programs

  • PARI
    A002810(n)={if(n>12, A002810(n-4*n=(n-1)\12*3)*10^n+10^n\9*7, [1, 7, 11, 27, 77, 107, 111, 127, 177, 777, 1127, 1177][n])} \\ Valid up to a(58) (or a(84) when long scale is used). - M. F. Hasler, Nov 03 2013

Formula

a(n+12) = a(n)*1000+777, as long as a(n+12) is less than one quadrillion (whatever scale is used). - M. F. Hasler, Nov 03 2013

Extensions

Edited and extended by M. F. Hasler, Nov 03 2013

A231072 Number of words in English spelling of n.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2
Offset: 0

Views

Author

M. F. Hasler, Nov 03 2013

Keywords

Comments

From a(101) on it must be made precise that this sequence uses the American style ("one hundred one"), as in A052360, and not the British style ("one hundred and one"). The choice of long or short scale does not make a difference since, e.g., the word "milliard" in long scale use would simply be replaced by "billion" in short scale. However, the use of "thousand [million]" instead, would lead to different results for numbers such that floor(n/10^6) mod 10^3 is zero. - M. F. Hasler, Nov 03 2013

Examples

			From "zero" to "twenty", the numbers are written in one word, so a(0..20)=1. "Twenty-one" is the first term to require 2 words, so a(21)=2.
		

Crossrefs

Programs

  • PARI
    a(n)=sum(k=7,#n=Vecsmall(English(n)),n[k-3]<65)+1 \\ See A052360 for English(). Only characters 4,...,length-4 need to be checked for space/hyphen since there is no word with less than 3 letters.
Showing 1-2 of 2 results.