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A073419 Worthless numbers: numbers without h, o, r, t, or w. 0
5, 6, 7, 9, 11, 55555, 66666, 77777, 99999, 555555, 666666, 777777, 999999, 5555555, 6666666, 7777777, 9999999, 555555555, 666666666, 777777777, 999999999, 1111111111, 55555555555, 66666666666, 77777777777, 99999999999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Of course there cannot be any number that is expressed in any of the usual ways without w, o, r, t or h, between eleven and a googol. "Twelve and the -teens and -ties, factorials" all contains at least one "t". Powers all contain "-to-the-". "Score" or "dozen" or "gross" contain at least an "o". "Hundred" and "thousand" contain at least an "h" and "-illion" contains an "o". Reading digit-by-digit would lead to the duller sequence: 5, 6, 7, 9, 55, 56, 57, 59 and exclude that very worthless number, five-elevens. - Michael Joseph Halm, May 05 2006

REFERENCES

M. J. Halm, Sequences (Re)discovered, Mpossibilities 81 (Aug. 2002).

LINKS

Table of n, a(n) for n=1..26.

EXAMPLE

a(1) = 5 because 5 is the first integer without an h, o, r, t or w.

a(6) = 55555 is the sixth worthless number, read as six-fives

CROSSREFS

Sequence in context: A287087 A180939 A229231 * A072956 A241203 A279001

Adjacent sequences:  A073416 A073417 A073418 * A073420 A073421 A073422

KEYWORD

easy,nonn,word,base

AUTHOR

Michael Joseph Halm, Aug 23 2002; corrected May 05 2006

EXTENSIONS

More terms from Michael Joseph Halm, May 05 2006

STATUS

approved

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Last modified June 27 15:07 EDT 2017. Contains 288790 sequences.