

A002810


Smallest number requiring n syllables in British English.
(Formerly M4341 N1818)


3



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
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,2


COMMENTS

This sequence uses British English as opposed to American English. a(6) = 107 since "one hundred and seven" has six syllables.  N. J. A. Sloane, Nov 24 2009
Contribution from M. F. Hasler, Nov 03 2013: (Start)
Because of this convention, we do not have A075774(a(n))=n, since A075774 uses American English, i.e., without the "trailing 'and'". All terms from a(6)=107 on will have this 'and', therefore A075774(a(n))=n1 for 5<n<18. From a(18)=107,777 on, there is a second 'and', etc. See A045736 for the "American English" version, see A001167 for the analog considering the number of words. (End)


REFERENCES

Rodolfo Kurchan, Mesmerizing Math. Puzzles, by Sterling Publications, page 18.
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).


LINKS

Table of n, a(n) for n=1..34.
Robert G. Wilson v, English names for the numbers from 0 to 11159 without spaces or hyphens.
Index to OEIS: sequences related to English words for n


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


EXAMPLE

"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.


PROG

(PARI) A002810(n)={if(n>12, A002810(n4*n=(n1)\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


CROSSREFS

Cf. A045736.
Sequence in context: A276504 A039287 A045222 * A045736 A158807 A067006
Adjacent sequences: A002807 A002808 A002809 * A002811 A002812 A002813


KEYWORD

word,nonn


AUTHOR

N. J. A. Sloane.


EXTENSIONS

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


STATUS

approved



